WO2015181969A1 - Metal foil for electromagnetic wave shielding, electromagnetic wave shielding member, and shielded cable - Google Patents

Metal foil for electromagnetic wave shielding, electromagnetic wave shielding member, and shielded cable Download PDF

Info

Publication number
WO2015181969A1
WO2015181969A1 PCT/JP2014/064473 JP2014064473W WO2015181969A1 WO 2015181969 A1 WO2015181969 A1 WO 2015181969A1 JP 2014064473 W JP2014064473 W JP 2014064473W WO 2015181969 A1 WO2015181969 A1 WO 2015181969A1
Authority
WO
WIPO (PCT)
Prior art keywords
layer
alloy layer
metal foil
electromagnetic wave
alloy
Prior art date
Application number
PCT/JP2014/064473
Other languages
French (fr)
Japanese (ja)
Inventor
田中　幸一郎
Original Assignee
Jx日鉱日石金属株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Jx日鉱日石金属株式会社 filed Critical Jx日鉱日石金属株式会社
Priority to PCT/JP2014/064473 priority Critical patent/WO2015181969A1/en
Publication of WO2015181969A1 publication Critical patent/WO2015181969A1/en

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C30/00—Coating with metallic material characterised only by the composition of the metallic material, i.e. not characterised by the coating process
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
    • C25D5/48—After-treatment of electroplated surfaces
    • C25D5/50—After-treatment of electroplated surfaces by heat-treatment
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D7/00—Electroplating characterised by the article coated
    • C25D7/06—Wires; Strips; Foils
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K9/00—Screening of apparatus or components against electric or magnetic fields

Definitions

  • the present invention relates to a metal foil used as an electromagnetic shielding material by laminating a resin layer or a resin film, and an electromagnetic shielding material and a shielded cable using the metal foil.
  • the Sn plating film is characterized by excellent corrosion resistance, good solderability and low contact resistance. For this reason, for example, Sn plating is used for metal foils, such as copper, as a composite material of a vehicle-mounted electromagnetic wave shielding material.
  • Sn plating is used for metal foils, such as copper, as a composite material of a vehicle-mounted electromagnetic wave shielding material.
  • stacked the resin layer or the film on one surface of the base material which consists of copper or copper alloy foil, and formed the Sn plating film on the other surface is used (refer patent document 1). ).
  • multilayer plated aluminum (alloy) foils with improved moisture resistance and corrosion resistance have been developed by forming a zinc displacement plating layer, an electro nickel plating layer, or an electro tin plating layer on the surface of aluminum or aluminum alloy foil. (See Patent Document 2).
  • the present invention has been made to solve the above-described problems, and an object of the present invention is to provide an electromagnetic shielding metal foil, an electromagnetic shielding material, and a shielded cable that have low contact resistance, excellent moisture resistance and corrosion resistance, and are less likely to generate Sn residue. And
  • the present inventors have formed an Sn alloy layer having a predetermined composition and thickness on the surface of the metal foil, thereby reducing the contact resistance, the moisture resistance and the corrosion resistance, and preventing the generation of Sn residue. Succeeded in obtaining metal foil.
  • the metal foil for electromagnetic shielding of the present invention has a Sn alloy layer made of Cu, Ni or Ag and Sn on one or both sides of a base material made of a metal foil having a thickness of 100 ⁇ m or less.
  • the Sn alloy layer thus formed contains 20 to 80% by mass of Sn and has a thickness of 30 to 1500 nm.
  • the microindentation hardness of the Sn alloy layer exceeds 500 MPa. It is preferable that the Sn alloy layer further contains one or more elements selected from the group consisting of P, W, Fe, Co, and Zn. Between the Sn alloy layer and the base material, a metal layer made of Cu, Ni or Ag, or an alloy layer made of Cu, Ni or Ag and P, W, Fe, Co or Zn. It is preferable that a formation is formed. It is preferable that an oxide layer of the Sn alloy layer is formed on the surface of the Sn alloy layer.
  • the base material is preferably made of gold, silver, platinum, stainless steel, iron, nickel, zinc, copper, a copper alloy, aluminum, or an aluminum alloy.
  • a resin layer is laminated on one side of the metal foil for electromagnetic wave shielding.
  • the resin layer is preferably a resin film.
  • the shielded cable of the present invention is shielded with the electromagnetic shielding material.
  • the present invention it is possible to obtain a metal foil for electromagnetic wave shielding that has low contact resistance, excellent moisture resistance and corrosion resistance, and hardly generates Sn residue.
  • % means “% by mass” unless otherwise specified.
  • the electromagnetic shielding metal foil 10 which concerns on the 1st Embodiment of this invention is the base material 1 which consists of metal foil, and the Sn alloy layer formed in the single side
  • the substrate 1 may be anything as long as it is a highly conductive metal that exhibits an electromagnetic wave shielding effect. Examples of the substrate 1 include a foil of gold, silver, platinum, stainless steel, iron, nickel, zinc, copper, copper alloy, aluminum, or aluminum alloy, but a copper or aluminum foil is common.
  • the formation method of the base material 1 is not specifically limited, For example, it may manufacture by rolling and you may form foil by electroplating.
  • the substrate 1 may be formed by dry plating on the surface of a resin layer or resin film of an electromagnetic wave shielding material described later.
  • the thickness of the substrate 1 is preferably determined in consideration of the frequency to be shielded by the electromagnetic wave and the skin effect. Specifically, it is preferable to set the skin depth to be equal to or greater than the skin depth obtained by substituting the conductivity of the elements constituting the substrate 1 and the target frequency into the following formula (1).
  • the skin depth is 6.61 ⁇ m
  • the thickness of the base material 1 is preferably about 7 ⁇ m or more.
  • the thickness of the substrate 1 is more preferably 4 to 50 ⁇ m, further preferably 5 to 25 ⁇ m.
  • d ⁇ 2 / (2 ⁇ ⁇ f ⁇ ⁇ ⁇ ⁇ ) ⁇ 1/2 (1)
  • d Epidermis depth ( ⁇ m)
  • f Frequency (GHz)
  • ⁇ Conductivity of conductor (S / m)
  • ⁇ Magnetic permeability of conductor (H / m)
  • electrolytic copper foil is manufactured by electrolytically depositing copper on a titanium or stainless steel drum from a copper sulfate plating bath or a copper cyanide plating bath. Manufactured.
  • oxygen-free copper JIS-H3100 (C1020)
  • tough pitch copper JIS-H3100 (C1100)
  • a copper alloy foil a well-known copper alloy can be used according to the required intensity
  • Known copper alloys include, for example, 0.01-0.3% tin-containing copper alloys and 0.01-0.05% silver-containing copper alloys. -0.12% Sn and Cu-0.02% Ag are often used.
  • a rolled copper foil having a conductivity of 5% or more can be used.
  • a well-known thing can be used as an electrolytic copper foil.
  • As the aluminum foil an aluminum foil having a purity of 99.0% or more can be used.
  • a well-known aluminum alloy can be used according to the required intensity
  • the Sn alloy layer is made of Ni, Cu or Ag, and Sn.
  • the Sn alloy layer contains 20 to 80% by mass of Sn and has a thickness of 30 to 1500 nm. Note that the composition and thickness of the Sn alloy layer, the underlayer, and the Sn oxide can be measured by a STEM described later.
  • the proportion of Sn in the Sn alloy layer is less than 20% by mass, the corrosion resistance of the Sn alloy layer decreases.
  • the proportion of Sn exceeds 80% by mass the hardness of the Sn alloy layer decreases and becomes too soft, and Sn residue is generated.
  • An alloy of Ni, Cu, or Ag and Sn has a lower contact resistance and higher corrosion resistance than other Sn alloys.
  • the corrosion resistance is lowered, and when it exceeds 1500 nm, cracks and cracks are generated on the surface of the Sn alloy layer to expose the base, and the corrosion resistance is similarly inferior.
  • the indentation hardness of the Sn alloy layer exceeds 500 MPa in accordance with ISO 14577-1, it is difficult to generate Sn residue, which is preferable.
  • the indentation hardness of the Sn alloy layer is more preferably 1200 MPa or more, and further preferably 2000 MPa or more.
  • the microindentation hardness of the Sn alloy layer is preferably 20000 MPa or less. If the hardness exceeds 20000 MPa, the Sn alloy layer may be cracked or cracked to expose the underlayer, resulting in poor corrosion resistance.
  • ISO 14577-1 defines a method of ultra-fine indentation hardness test.
  • the Sn alloy layer may further contain one or more elements selected from the group consisting of P, W, Fe, Co, and Zn. When the Sn alloy layer contains these elements, the layer can be hardened.
  • the total proportion of the above elements in the Sn alloy layer is preferably 1 to 40% by mass, and more preferably 5 to 30% by mass.
  • the Sn alloy layer can be formed by alloy plating (wet plating), sputtering using an alloy target constituting the alloy layer, vapor deposition using a component constituting the alloy layer, or the like. Further, as shown in FIG. 1A, for example, a first layer 21 made of an element other than Sn is first formed on one surface of the substrate 1, and a second layer 22 made of Sn is formed on the surface of the first layer 21. After the formation, the element of the first layer 21 can be diffused in the second layer 22 by heat treatment to form the Sn alloy layer 2 shown in FIG.
  • the heat treatment conditions are not particularly limited. For example, the heat treatment can be performed at 120 to 500 ° C. for about 2 seconds to 10 hours.
  • the metal foil 11 for electromagnetic wave shielding which concerns on the 2nd Embodiment of this invention is demonstrated.
  • the base layer 3 is further formed between the base material 1 and the Sn alloy layer 2 in the electromagnetic shielding metal foil 10 according to the first embodiment.
  • the underlayer 3 prevents the diffusion of the element in the base material, and the ratio of Sn in the Sn alloy layer And it becomes easy to control the hardness of the Sn alloy layer.
  • the underlayer 3 is composed of (1) a metal layer made of Cu, Ni or Ag, or (2) an alloy layer made of Ni, Cu or Ag and P, W, Fe, Co or Zn.
  • An example of (2) is a Ni—Zn alloy layer.
  • the underlayer 3 can be formed, for example, by increasing the thickness of the first layer 21 in FIG. 1A and leaving a part of the first layer 21 without the Sn alloy layer 2 after the heat treatment.
  • the underlayer 3 and the Sn alloy layer 2 may be formed directly on the surface of the base material 1 by plating or the like in this order without heat treatment.
  • the underlayer 3 and the Sn alloy layer 2 can also be formed by vapor deposition, PVD, CVD, etc., in addition to wet plating.
  • a zinc substitution plating layer may be formed between the base layer 3 and the base material 1 as the base plating for electroplating the base layer 3.
  • Sn oxide is formed on the surface of the Sn alloy layer.
  • Sn oxide has high corrosion resistance.
  • the corrosion resistance of the Sn alloy layer is further improved.
  • FIG. 1A when the Sn alloy layer is formed by heating, Sn oxide is formed in the second layer 22 by natural oxidation when the second layer 22 made of Sn is formed, and thereafter Even in the alloying by heating, the Sn alloy layer remains.
  • This Sn oxide has an effect of improving characteristics such as corrosion resistance.
  • the Sn oxide does not have to be a layer and may be present on the surface of the Sn alloy layer, but a thickness of 2 to 30 nm is preferable.
  • the contact resistance increases when the thickness of the layer exceeds 30 nm. Note that it is preferable to form the Sn alloy layer by heat treatment because a thick Sn oxide layer is positively formed during the heat treatment.
  • the electromagnetic shielding material 100 is formed by laminating an electromagnetic shielding metal foil 10 and a resin layer or a resin film 4 on one surface of the metal foil 10.
  • a resin such as polyimide can be used as the resin layer
  • a film of PET (polyethylene terephthalate) or PEN (polyethylene naphthalate) can be used as the resin film.
  • the resin layer and the resin film may be bonded to the metal foil with an adhesive, but the molten resin may be cast on the metal foil without using the adhesive, or the film may be thermocompression bonded to the metal foil.
  • a film in which a copper or aluminum layer is directly formed on a resin film by PVD or CVD, or a thin layer of copper or aluminum is formed on a resin film by PVD or CVD as a conductive layer You may use the metallized film which formed the metal layer thickly by wet plating.
  • a well-known thing can be used as a resin layer or a resin film.
  • the thickness of the resin layer or the resin film is not particularly limited, but a resin layer having a thickness of, for example, 1 to 100 ⁇ m, more preferably 3 to 50 ⁇ m can be suitably used. When an adhesive is used, the thickness of the adhesive layer can be set to 10 ⁇ m or less, for example.
  • the thickness of the electromagnetic shielding material 100 is preferably 1.0 mm or less, more preferably 0.01 to 0.5 mm.
  • a shielded cable is obtained by winding the electromagnetic wave shielding material 100 around the outside of the cable.
  • the aluminum foil As the aluminum foil, a 12 ⁇ m thick aluminum foil (manufactured by Sun Aluminum Industry Co., Ltd.) was used.
  • the Al metallized film As the Al metallized film, a 12 ⁇ m-thick PET film (manufactured by Toyobo Co., Ltd.) with 6 ⁇ m of aluminum formed by vacuum deposition was used.
  • Sn alloy layer An Sn alloy layer was formed on one side of the substrate.
  • Table 1 shows a method for forming the Sn alloy layer.
  • plating means that the first layer 21 and the second layer 22 were plated in this order by the method shown in FIG. 1A and then heat-treated at 150 to 180 ° C. for 2 to 7 hours in a nitrogen atmosphere. When the first layer 21 remained after the heat treatment, the composition is shown in Table 1 with the layer as an underlayer.
  • Platinum only means that an Sn layer was formed by plating and no heat treatment was performed.
  • alloy plating is the one in which an Sn alloy layer was formed by alloy plating, and the base layer was plated on the substrate before alloy plating.
  • the Ni alloy plating shown in Table 1 was formed as an underlayer on one side of the base material, and then Sn plating was performed on the underlayer. Further, the Sn alloy layer was formed by heat treatment under the above conditions. Formed. At this time, elements other than Ni (P, W, Fe, Co) were also diffused from the base layer, and an Sn alloy layer containing three components was formed.
  • a base Ni layer is formed on the Zn layer, a Sn plating is applied on the base Ni layer, and a Sn alloy layer is further formed by heat treatment. Formed.
  • Example 20 in which the thickness of the Ni layer was reduced, Zn was also diffused from the Zn layer into the Sn layer on the surface, and a Sn—Ni—Zn alloy layer containing three components was formed.
  • Comparative Example 8 after a Zn layer was formed on the aluminum foil by displacement plating, a base Ni layer was plated on the Zn layer, and Sn plating was applied on the base Ni layer.
  • Ni plating Ni sulfate bath (Ni concentration: 20 g / L, current density: 2 to 10 A / dm 2 )
  • Sn plating phenol sulfonic acid Sn bath (Sn concentration: 40 g / L, current density: 2 to 10 A / dm 2 )
  • Cu plating Cu sulfate bath (Cu concentration: 20 g / L, current density: 2 to 10 A / dm 2 )
  • Zn displacement plating zincate bath (Zn concentration: 15 g / L)
  • Ni—Sn plating: pyrophosphate bath Ni concentration 10 g / L, Sn concentration 10 g / L, current density: 0.1 to 2 A / dm 2
  • Co—Sn plating pyrophosphate bath (Co concentration 20 g
  • Ni-P sulfuric acid bath (Ni concentration: 20 g / L, P concentration: 20 g / L, current density: 2-4 A / dm 2 )
  • Ni—W sulfuric acid bath (Ni concentration: 20 g / L, W concentration: 20 g / L, current density: 0.1 to 2 A / dm 2 )
  • Ni—Fe sulfuric acid bath (Ni concentration: 20 g / L, Fe concentration: 10 g / L, current density: 0.1 to 2 A / dm 2 )
  • Ni—Co sulfuric acid bath (Ni concentration: 20 g / L, Co concentration: 10 g / L, current density: 0.1 to 2 A / dm 2 )
  • “Sputtering” is a heat treatment after sputtering of Ni and Sn in this order.
  • alloy sputtering is an alloy layer formed by sputtering using a target material of a corresponding alloy.
  • the layer formed by alloy sputtering has the composition of the alloy layer itself, no heat treatment was performed. Sputtering and alloy sputtering were performed under the following conditions.
  • Sputtering equipment Batch type sputtering equipment (ULVAC, Model MNS-6000) Sputtering conditions: ultimate vacuum 1.0 ⁇ 10 ⁇ 5 Pa, sputtering pressure 0.2 Pa, sputtering power 50 W
  • Vapor deposition equipment Vacuum vapor deposition equipment (ULVAC, model MB05-1006) Deposition conditions: ultimate vacuum 5.0 ⁇ 10 ⁇ 3 Pa, electron beam acceleration voltage 6 kV Deposition source: Ni (purity 3N)
  • the cross-sectional sample of the obtained metal foil for electromagnetic wave shielding was subjected to line analysis by STEM (scanning transmission electron microscope, JEM-2100F manufactured by JEOL Ltd.) to determine the layer configuration.
  • the analyzed designated elements are Sn, Ag, Ni, Cu, P, W, Fe, Co, Zn, C, S and O. Further, the ratio (wt%) of each element in each layer was analyzed with the total of the specified elements described above being 100% (acceleration voltage: 200 kV, measurement interval: 2 nm). As shown in FIG.
  • a layer containing 5 wt% or more of Sn and containing 5 wt% or more of any element of Ag, Ni, and Cu is an Sn alloy layer, and the thickness is shown in FIG. Response).
  • a layer that is located on the lower layer side of the Sn alloy layer and has Sn of less than 5 wt% and containing any element of Ag, Ni, and Cu in an amount of 5 wt% or more was used as a base layer, and the thickness thereof was determined on the drawing.
  • the layer located on the upper layer side from the Sn alloy layer and having Sn of 5 wt% or more and O of 5 wt% or more was defined as an Sn oxide layer, and the thickness thereof was determined on the drawing.
  • the STEM measurement was performed in 3 fields of view, and the average value of 3 fields ⁇ 5 locations was defined as the thickness of each layer.
  • composition of Sn alloy layer and underlayer The composition of the Sn alloy layer and the underlayer was determined by line analysis using STEM (scanning transmission electron microscope). The elements constituting the Sn alloy layer and the underlayer were designated elements, and the mass ratio of each element when the total of the designated elements was 100% was defined as the composition of the Sn alloy layer and the underlayer. (Measurement of hardness) The surface of the obtained metal foil for electromagnetic wave shielding on the Sn alloy layer side was measured for hardness by an ultra-fine indentation hardness test in accordance with ISO14577-1. ENT-2100 made by Elionix was used for the measurement of hardness.
  • the surface on the alloy layer side of the obtained metal foil for electromagnetic shielding was subjected to a salt spray test, and the contact resistance of the outermost surface on the Sn alloy layer side before and after the test was measured.
  • the contact resistance was measured by a four-terminal method using an electrical contact simulator CRS-1 manufactured by Yamazaki Seiki Co., Ltd. Probe: gold probe, contact load: 20 gf, bias current: 10 mA, sliding distance: 1 mm
  • the salt spray test was in accordance with JIS-Z2371 (temperature: 35 ° C., salt water component: sodium chloride, salt water concentration: 5 wt%, spray pressure: 98 ⁇ 10 kPa, spray time: 48 h).
  • the initial contact resistance before the salt spray test indicates the evaluation of the contact resistance itself, and the contact resistance after the salt spray test indicates the evaluation of corrosion resistance.
  • ⁇ Contact resistance is less than 20 m ⁇ ⁇ : Contact resistance is 20 m ⁇ or more, less than 100 m ⁇ ⁇ : Contact resistance is 100 m ⁇ or more
  • each of the examples has an Sn alloy layer comprising Cu, Ni or Ag and Sn on the surface of the base material, containing 20 to 80% by mass of Sn and having a thickness of 30 to 1500 nm.
  • the contact resistance was low, the corrosion resistance was excellent, and Sn residue was hardly generated.
  • the corrosion resistance was more excellent in Examples 1 to 12 and 16 to 20 where the Sn oxide layer was thicker than the other examples.
  • 4 and 5 show a cross-sectional image of the sample of Example 1 by STEM and the result of line analysis by STEM, respectively.
  • the X layer and Y layer in the cross-sectional image are found to be a Ni—Sn alloy layer (Sn alloy layer) and a Ni layer (underlayer) from the results of the line analysis, respectively.
  • Comparative Example 5 In Comparative Example 5 in which the Sn—Co layer was formed as the Sn alloy layer, Sn debris was hardly generated, but the contact resistance was high and the corrosion resistance was poor.
  • Comparative Examples 6 to 8 in which a pure Sn layer was provided instead of the Sn alloy layer, the Sn layer had a hardness of 500 MPa or less, and Sn residue was remarkably generated.
  • Comparative Example 9 in which the Ni layer was formed instead of the Sn alloy layer, the corrosion resistance was inferior.
  • Comparative Example 10 in which the Sn ratio in the Sn alloy layer was less than 20% by mass, the contact resistance was high and the corrosion resistance was inferior. Further, the Sn alloy layer had a hardness of 500 MPa or less, and Sn residue was remarkably generated.

Abstract

[Problem] To provide: a metal foil that is for electromagnetic wave shielding, has low contact resistance, has superior moisture resistance and corrosion resistance, and does not easily generate Sn gas; an electromagnetic wave shielding member, and a shielded cable. [Solution] In the metal foil (10) for electromagnetic wave shielding, an Sn alloy layer (2) comprising Cu, Ni, or Ag, and Sn is formed on one or both sides of a substrate comprising a metal foil (1) having a thickness no greater than 100 μm, and the Sn alloy layer contains 20-80 mass% of Sn and has a thickness of 30-1500 nm.

Description

電磁波シールド用金属箔、電磁波シールド材及びシールドケーブルMetal foil for electromagnetic wave shielding, electromagnetic wave shielding material and shielded cable
　本発明は、樹脂層又は樹脂フィルムを積層されて電磁波シールド材に用いられる金属箔、それを用いた電磁波シールド材及びシールドケーブルに関する。 The present invention relates to a metal foil used as an electromagnetic shielding material by laminating a resin layer or a resin film, and an electromagnetic shielding material and a shielded cable using the metal foil.
　Ｓｎめっき被膜は耐食性に優れ、かつ、はんだ付け性が良好で接触抵抗が低いと言う特徴を持っている。このため、例えば、車載電磁波シールド材の複合材料として、銅等の金属箔にＳｎめっきされて使用されている。
　上記の複合材料としては、銅又は銅合金箔からなる基材の一方の面に樹脂層又はフィルムを積層し、他の面にＳｎめっき被膜を形成した構造が用いられている（特許文献１参照）。
　又、アルミニウム又はアルミニウム合金箔の表面に亜鉛置換めっき層、電気ニッケルめっき層、又は電気スズめっき層を形成することで、耐湿性、耐食性を改善した多層めっきアルミニウム（合金）箔が開発されている（特許文献２参照）。 The Sn plating film is characterized by excellent corrosion resistance, good solderability and low contact resistance. For this reason, for example, Sn plating is used for metal foils, such as copper, as a composite material of a vehicle-mounted electromagnetic wave shielding material.
As said composite material, the structure which laminated | stacked the resin layer or the film on one surface of the base material which consists of copper or copper alloy foil, and formed the Sn plating film on the other surface is used (refer patent document 1). ).
In addition, multilayer plated aluminum (alloy) foils with improved moisture resistance and corrosion resistance have been developed by forming a zinc displacement plating layer, an electro nickel plating layer, or an electro tin plating layer on the surface of aluminum or aluminum alloy foil. (See Patent Document 2).
　ところで、Ｓｎめっきは柔らかいため、金属箔の製造時等に削れてＳｎカスが発生する。このＳｎカスは金属箔の生産ラインの搬送ロールに付着、堆積したり、粒状になって金属箔表面の傷や凹凸の原因となる。Ｓｎカスを除去するためには、生産ラインを停止して定期的に清掃が必要となり、生産性が低下する。
　Ｓｎカスを防止するためには、Ｓｎめっき被膜を硬くすることが有効であると考えられる。このようなことから、Ｓｎめっき被膜中のＣ濃度を調整して被膜を硬くする方法が知られている（特許文献３参照）。 By the way, since Sn plating is soft, it scrapes at the time of manufacture of metal foil etc., and Sn residue is generated. This Sn residue adheres to and accumulates on the transport roll of the metal foil production line, or becomes granular and causes scratches and irregularities on the surface of the metal foil. In order to remove Sn residue, it is necessary to stop the production line and perform periodic cleaning, which reduces productivity.
In order to prevent Sn residue, it is considered effective to harden the Sn plating film. For this reason, there is known a method of adjusting the C concentration in the Sn plating film to harden the film (see Patent Document 3).
国際公開ＷＯ２００９／１４４９７３号International publication WO2009 / 144773 特開２０１３―００７０９２号公報JP 2013-007092 A 特許第２９７１０３５号公報Japanese Patent No. 2971035
　しかしながら、金属箔は柔らかいため、その表面に硬いＳｎ層を形成すると、Ｓｎ層が金属箔の柔軟性に追従しきれなくなってクラックを生じ、Ｓｎ層本来の目的である耐湿性、耐食性が損なわれる。
　本発明は上記課題を解決するためになされたものであり、接触抵抗が低く、耐湿、耐食性に優れ、かつＳｎカスが発生しにくい電磁波シールド用金属箔、電磁波シールド材及びシールドケーブルの提供を目的とする。 However, since the metal foil is soft, if a hard Sn layer is formed on the surface of the metal foil, the Sn layer cannot follow the flexibility of the metal foil, causing cracks, and the moisture resistance and corrosion resistance, which are the original purposes of the Sn layer, are impaired. .
The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an electromagnetic shielding metal foil, an electromagnetic shielding material, and a shielded cable that have low contact resistance, excellent moisture resistance and corrosion resistance, and are less likely to generate Sn residue. And
　本発明者らは種々検討した結果、金属箔の表面に所定の組成と厚みのＳｎ合金層を形成することで、接触抵抗が低く、耐湿、耐食性に優れ、かつＳｎカスが発生しにくい電磁波シールド用金属箔を得ることに成功した。 As a result of various investigations, the present inventors have formed an Sn alloy layer having a predetermined composition and thickness on the surface of the metal foil, thereby reducing the contact resistance, the moisture resistance and the corrosion resistance, and preventing the generation of Sn residue. Succeeded in obtaining metal foil.
　上記の目的を達成するために、本発明の電磁波シールド用金属箔は、厚さ１００μｍ以下の金属箔からなる基材の片面又は両面に、Ｃｕ、Ｎｉ又はＡｇとＳｎとからなるＳｎ合金層が形成され、該Ｓｎ合金層は、Ｓｎを２０～８０質量％含み、かつ厚さが３０～１５００ｎｍである。 In order to achieve the above object, the metal foil for electromagnetic shielding of the present invention has a Sn alloy layer made of Cu, Ni or Ag and Sn on one or both sides of a base material made of a metal foil having a thickness of 100 μm or less. The Sn alloy layer thus formed contains 20 to 80% by mass of Sn and has a thickness of 30 to 1500 nm.
　前記Ｓｎ合金層の微小押し込み硬さが５００ＭＰａを超えることが好ましい。
　前記Ｓｎ合金層がさらに、Ｐ、Ｗ、Ｆｅ、Ｃｏ及びＺｎの群から選ばれる１種以上の元素を含むことが好ましい。
　前記Ｓｎ合金層と前記基材との間に、Ｃｕ、Ｎｉ若しくはＡｇからなる金属層、又はＣｕ、Ｎｉ若しくはＡｇと、Ｐ、Ｗ、Ｆｅ、Ｃｏ若しくはＺｎとからなる合金層によって構成される下地層が形成されていることが好ましい。
　前記Ｓｎ合金層の表面に、Ｓｎ合金層の酸化物層が形成されていることが好ましい。
　前記基材が金、銀、白金、ステンレス、鉄、ニッケル、亜鉛、銅、銅合金、アルミニウム、又はアルミニウム合金からなることが好ましい。 It is preferable that the microindentation hardness of the Sn alloy layer exceeds 500 MPa.
It is preferable that the Sn alloy layer further contains one or more elements selected from the group consisting of P, W, Fe, Co, and Zn.
Between the Sn alloy layer and the base material, a metal layer made of Cu, Ni or Ag, or an alloy layer made of Cu, Ni or Ag and P, W, Fe, Co or Zn. It is preferable that a formation is formed.
It is preferable that an oxide layer of the Sn alloy layer is formed on the surface of the Sn alloy layer.
The base material is preferably made of gold, silver, platinum, stainless steel, iron, nickel, zinc, copper, a copper alloy, aluminum, or an aluminum alloy.
　本発明の電磁波シールド材は、前記電磁波シールド用金属箔の片面に、樹脂層が積層されている。
　前記樹脂層は樹脂フィルムであることが好ましい。 In the electromagnetic wave shielding material of the present invention, a resin layer is laminated on one side of the metal foil for electromagnetic wave shielding.
The resin layer is preferably a resin film.
　本発明のシールドケーブルは、前記電磁波シールド材でシールドされてなる。 The shielded cable of the present invention is shielded with the electromagnetic shielding material.
　本発明によれば、接触抵抗が低く、耐湿、耐食性に優れ、かつＳｎカスが発生しにくい電磁波シールド用金属箔が得られる。 According to the present invention, it is possible to obtain a metal foil for electromagnetic wave shielding that has low contact resistance, excellent moisture resistance and corrosion resistance, and hardly generates Sn residue.
本発明の第１の実施の形態に係る電磁波シールド用金属箔を示す断面図である。It is sectional drawing which shows the metal foil for electromagnetic wave shielding which concerns on the 1st Embodiment of this invention. 本発明の第２の実施の形態に係る電磁波シールド用金属箔を示す断面図である。It is sectional drawing which shows the metal foil for electromagnetic wave shielding which concerns on the 2nd Embodiment of this invention. 本発明の実施の形態に係る電磁波シールド材を示す断面図である。It is sectional drawing which shows the electromagnetic wave shielding material which concerns on embodiment of this invention. 実施例４の試料のＳＴＥＭによる断面像を示す図である。It is a figure which shows the cross-sectional image by STEM of the sample of Example 4. FIG. 実施例４の試料のＳＴＥＭによる線分析の結果を示す図である。It is a figure which shows the result of the line analysis by STEM of the sample of Example 4. Ｓｎカスの試験装置を示す図である。It is a figure which shows the test apparatus of Sn residue.
　以下、本発明の実施の形態について説明する。なお、本発明において％とは、特に断らない限り、質量％を示すものとする。 Hereinafter, embodiments of the present invention will be described. In the present invention, “%” means “% by mass” unless otherwise specified.
　図１（ｂ）に示すように、本発明の第１の実施の形態に係る電磁波シールド用金属箔１０は、金属箔からなる基材１と、基材１の片面に形成されたＳｎ合金層２とを有する。
（基材）
　基材１は、電磁波シールド効果を発揮する導電性の高い金属であればなんでもよい。基材１としては金、銀、白金、ステンレス、鉄、ニッケル、亜鉛、銅、銅合金、アルミニウム、又はアルミニウム合金などの箔が挙げられるが、銅又はアルミニウムの箔が一般的である。
　基材１の形成方法は特に限定されず、例えば圧延して製造してもよく、電気めっきで箔を形成してもよい。又、後述する電磁波シールド材の樹脂層又は樹脂フィルムの表面に、乾式めっきして基材１を成膜してもよい。
　基材１の厚みは、電磁波シールドの対象とする周波数と表皮効果を考慮して決定するのがよい。具体的には、基材１を構成する元素の導電率と、対象となる周波数を下式（１）に代入して得られる表皮深さ以上とするのが好ましい。例えば、基材１として銅箔を使用し、対象となる周波数が１００ＭＨｚの場合、表皮深さは６．６１μｍであるので、基材１の厚みを約７μｍ以上とするのがよい。基材１の厚みが厚くなると、柔軟性や加工性に劣り、原料コストも増加することから１００μｍ以下とする。基材１の厚みは４～５０μｍがより好ましく、５～２５μｍがさらに好ましい。
　　ｄ＝｛２／（２π×ｆ×σ×μ）｝１／２　　　　（１）
ｄ：表皮深さ（μｍ）
ｆ：周波数（ＧＨｚ）
σ：導体の導電率（Ｓ／ｍ）
μ：導体の透磁率（Ｈ／ｍ） As shown in FIG.1 (b), the electromagnetic shielding metal foil 10 which concerns on the 1st Embodiment of this invention is the base material 1 which consists of metal foil, and the Sn alloy layer formed in the single side | surface of the base material 1 2.
(Base material)
The substrate 1 may be anything as long as it is a highly conductive metal that exhibits an electromagnetic wave shielding effect. Examples of the substrate 1 include a foil of gold, silver, platinum, stainless steel, iron, nickel, zinc, copper, copper alloy, aluminum, or aluminum alloy, but a copper or aluminum foil is common.
The formation method of the base material 1 is not specifically limited, For example, it may manufacture by rolling and you may form foil by electroplating. Alternatively, the substrate 1 may be formed by dry plating on the surface of a resin layer or resin film of an electromagnetic wave shielding material described later.
The thickness of the substrate 1 is preferably determined in consideration of the frequency to be shielded by the electromagnetic wave and the skin effect. Specifically, it is preferable to set the skin depth to be equal to or greater than the skin depth obtained by substituting the conductivity of the elements constituting the substrate 1 and the target frequency into the following formula (1). For example, when copper foil is used as the base material 1 and the target frequency is 100 MHz, the skin depth is 6.61 μm, so the thickness of the base material 1 is preferably about 7 μm or more. When the thickness of the base material 1 is increased, the flexibility and workability are inferior, and the raw material cost is increased. The thickness of the substrate 1 is more preferably 4 to 50 μm, further preferably 5 to 25 μm.
d = {2 / (2π × f × σ × μ)} 1/2 (1)
d: Epidermis depth (μm)
f: Frequency (GHz)
σ: Conductivity of conductor (S / m)
μ: Magnetic permeability of conductor (H / m)
　基材１として銅箔を用いる場合、銅箔の種類に特に制限はないが、典型的には圧延銅箔や電解銅箔の形態で用いることができる。一般的には、電解銅箔は硫酸銅めっき浴やシアン化銅めっき浴からチタン又はステンレスのドラム上に銅を電解析出して製造され、圧延銅箔は圧延ロールによる塑性加工と熱処理を繰り返して製造される。
　圧延銅箔としては、純度９９．９％以上の無酸素銅（ＪＩＳ-Ｈ３１００（Ｃ１０２０））又はタフピッチ銅（ＪＩＳ-Ｈ３１００（Ｃ１１００））を用いることができる。又、銅合金箔としては要求される強度や導電性に応じて公知の銅合金を用いることができる。公知の銅合金としては、例えば、０．０１～０．３％の錫入り銅合金や０．０１～０．０５％の銀入り銅合金が挙げられ、特に、導電性に優れたものとしてＣｕ-０．１２％Ｓｎ、Ｃｕ-０．０２％Ａｇがよく用いられる。例えば、圧延銅箔として導電率が５％以上のものを用いることができる。電解銅箔としては、公知のものを用いることができる。
　又、アルミニウム箔としては、純度９９．０％以上のアルミニウム箔を用いることができる。又、アルミニウム合金箔としては、要求される強度や導電率に応じて公知のアルミニウム合金を用いることができる。公知のアルミニウム合金としては、例えば、０．０１～０．１５％のＳｉと０．０１～１．０％のＦｅ入りのアルミニウム合金、１．０～１．５％のＭｎ入りアルミニウム合金が挙げられる。 When using copper foil as the base material 1, although there is no restriction | limiting in particular in the kind of copper foil, Typically, it can use with the form of rolled copper foil or electrolytic copper foil. In general, electrolytic copper foil is manufactured by electrolytically depositing copper on a titanium or stainless steel drum from a copper sulfate plating bath or a copper cyanide plating bath. Manufactured.
As the rolled copper foil, oxygen-free copper (JIS-H3100 (C1020)) or tough pitch copper (JIS-H3100 (C1100)) having a purity of 99.9% or more can be used. Moreover, as a copper alloy foil, a well-known copper alloy can be used according to the required intensity | strength and electroconductivity. Known copper alloys include, for example, 0.01-0.3% tin-containing copper alloys and 0.01-0.05% silver-containing copper alloys. -0.12% Sn and Cu-0.02% Ag are often used. For example, a rolled copper foil having a conductivity of 5% or more can be used. A well-known thing can be used as an electrolytic copper foil.
As the aluminum foil, an aluminum foil having a purity of 99.0% or more can be used. Moreover, as an aluminum alloy foil, a well-known aluminum alloy can be used according to the required intensity | strength and electrical conductivity. Examples of known aluminum alloys include aluminum alloys containing 0.01 to 0.15% Si and 0.01 to 1.0% Fe, and aluminum alloys containing 1.0 to 1.5% Mn. It is done.
（Ｓｎ合金層）
　Ｓｎ合金層は、Ｎｉ、Ｃｕ又はＡｇと、Ｓｎとからなる。Ｓｎ合金層は、Ｓｎを２０～８０質量％含み、かつ厚さが３０～１５００ｎｍである。
　なお、Ｓｎ合金層、下地層、Ｓｎ酸化物の組成及び厚みは、後述するＳＴＥＭによって測定することができる。
　Ｓｎ合金層中のＳｎの割合が２０質量％未満であると、Ｓｎ合金層の耐食性が低下する。一方、Ｓｎの割合が８０質量％を超えると、Ｓｎ合金層の硬さが低下して柔らかくなり過ぎ、Ｓｎカスが発生する。
　Ｎｉ、Ｃｕ、又はＡｇと、Ｓｎとの合金は、他のＳｎ合金に比べて接触抵抗が低く、耐食性も高い。
　Ｓｎ合金層の厚さが３０ｎｍ未満であると耐食性が低下し、１５００ｎｍを超えるとＳｎ合金層表面に割れやクラックが発生して下地が露出し、同様に耐食性が劣る。
　Ｓｎ合金層のＩＳＯ１４５７７－１に準拠した微小押し込み硬さが５００ＭＰａを超えると、Ｓｎカスが発生し難くなるので好ましい。Ｓｎ合金層の微小押し込み硬さが１２００ＭＰａ以上であるとより好ましく、２０００ＭＰａ以上であるとさらに好ましい。また、Ｓｎ合金層の微小押し込み硬さは２００００ＭＰａ以下が望ましい。硬さが２００００ＭＰａを超えると、Ｓｎ合金層に割れやクラックが発生して下地が露出し、耐食性が劣ることがある。
　なお、ＩＳＯ１４５７７－１には、超微小押し込み硬さ試験の方法が規定されている。 (Sn alloy layer)
The Sn alloy layer is made of Ni, Cu or Ag, and Sn. The Sn alloy layer contains 20 to 80% by mass of Sn and has a thickness of 30 to 1500 nm.
Note that the composition and thickness of the Sn alloy layer, the underlayer, and the Sn oxide can be measured by a STEM described later.
When the proportion of Sn in the Sn alloy layer is less than 20% by mass, the corrosion resistance of the Sn alloy layer decreases. On the other hand, when the proportion of Sn exceeds 80% by mass, the hardness of the Sn alloy layer decreases and becomes too soft, and Sn residue is generated.
An alloy of Ni, Cu, or Ag and Sn has a lower contact resistance and higher corrosion resistance than other Sn alloys.
When the thickness of the Sn alloy layer is less than 30 nm, the corrosion resistance is lowered, and when it exceeds 1500 nm, cracks and cracks are generated on the surface of the Sn alloy layer to expose the base, and the corrosion resistance is similarly inferior.
When the indentation hardness of the Sn alloy layer exceeds 500 MPa in accordance with ISO 14577-1, it is difficult to generate Sn residue, which is preferable. The indentation hardness of the Sn alloy layer is more preferably 1200 MPa or more, and further preferably 2000 MPa or more. Further, the microindentation hardness of the Sn alloy layer is preferably 20000 MPa or less. If the hardness exceeds 20000 MPa, the Sn alloy layer may be cracked or cracked to expose the underlayer, resulting in poor corrosion resistance.
Note that ISO 14577-1 defines a method of ultra-fine indentation hardness test.
　Ｓｎ合金層はさらに、Ｐ、Ｗ、Ｆｅ、Ｃｏ及びＺｎの群から選ばれる１種以上の元素を含んでもよい。Ｓｎ合金層がこれら元素を含むと、層を硬くすることができる。Ｓｎ合金層中の上記元素の合計割合は、１～４０質量％が好ましく、５～３０質量％がさらに好ましい。 The Sn alloy layer may further contain one or more elements selected from the group consisting of P, W, Fe, Co, and Zn. When the Sn alloy layer contains these elements, the layer can be hardened. The total proportion of the above elements in the Sn alloy layer is preferably 1 to 40% by mass, and more preferably 5 to 30% by mass.
（Ｓｎ合金層の形成方法）
　Ｓｎ合金層は、合金めっき（湿式めっき）、合金層を構成する合金のターゲットを用いたスパッタ、合金層を構成する成分を用いた蒸着等によって形成することができる。
　又、図１（ａ）に示すように、例えば、基材１の片面にまずＳｎ以外の元素からなる第１層２１を形成し、第１層２１の表面にＳｎからなる第２層２２を形成した後、熱処理して第１層２１の元素を第２層２２中に拡散させ、図１（ｂ）に示すＳｎ合金層２を形成することもできる。熱処理の条件は特に限定されないが、例えば、１２０～５００℃で２秒～１０時間程度とすることができる。 (Method for forming Sn alloy layer)
The Sn alloy layer can be formed by alloy plating (wet plating), sputtering using an alloy target constituting the alloy layer, vapor deposition using a component constituting the alloy layer, or the like.
Further, as shown in FIG. 1A, for example, a first layer 21 made of an element other than Sn is first formed on one surface of the substrate 1, and a second layer 22 made of Sn is formed on the surface of the first layer 21. After the formation, the element of the first layer 21 can be diffused in the second layer 22 by heat treatment to form the Sn alloy layer 2 shown in FIG. The heat treatment conditions are not particularly limited. For example, the heat treatment can be performed at 120 to 500 ° C. for about 2 seconds to 10 hours.
　次に、図２を参照し、本発明の第２の実施の形態に係る電磁波シールド用金属箔１１について説明する。電磁波シールド用金属箔１１は、第１の実施の形態に係る電磁波シールド用金属箔１０において、さらに基材１とＳｎ合金層２との間に、下地層３が形成されている。
　熱処理によってＳｎ合金層を形成する場合、基材中の元素がＳｎ合金層に拡散する場合があるが、下地層３は基材中の元素の拡散を防止し、Ｓｎ合金層中のＳｎの割合やＳｎ合金層の硬さをコントロールしやすくなる。
　下地層３は、（１）Ｃｕ、Ｎｉ若しくはＡｇからなる金属層、又は（２）Ｎｉ、Ｃｕ若しくはＡｇと、Ｐ、Ｗ、Ｆｅ、Ｃｏ若しくはＺｎとからなる合金層、によって構成されている。（２）の例としては、Ｎｉ－Ｚｎ合金層が挙げられる。
　下地層３は、例えば図１（ａ）の第１層２１の厚みを厚くし、熱処理後に第１層２１の一部をＳｎ合金層２とせずに残存させることで形成することができる。勿論、基材１の表面に、熱処理せずに直接下地層３、Ｓｎ合金層２をこの順にめっき等で形成してもよい。又、下地層３、Ｓｎ合金層２は、湿式めっきの他、蒸着、ＰＶＤ、ＣＶＤ等によって形成することもできる。
　又、基材としてアルミニウムやアルミニウム合金箔を使用する場合、下地層３を電気めっきするための下地めっきとして、下地層３と基材１との間に亜鉛置換めっき層を形成してもよい。 Next, with reference to FIG. 2, the metal foil 11 for electromagnetic wave shielding which concerns on the 2nd Embodiment of this invention is demonstrated. In the electromagnetic shielding metal foil 11, the base layer 3 is further formed between the base material 1 and the Sn alloy layer 2 in the electromagnetic shielding metal foil 10 according to the first embodiment.
When the Sn alloy layer is formed by heat treatment, the element in the base material may diffuse into the Sn alloy layer, but the underlayer 3 prevents the diffusion of the element in the base material, and the ratio of Sn in the Sn alloy layer And it becomes easy to control the hardness of the Sn alloy layer.
The underlayer 3 is composed of (1) a metal layer made of Cu, Ni or Ag, or (2) an alloy layer made of Ni, Cu or Ag and P, W, Fe, Co or Zn. An example of (2) is a Ni—Zn alloy layer.
The underlayer 3 can be formed, for example, by increasing the thickness of the first layer 21 in FIG. 1A and leaving a part of the first layer 21 without the Sn alloy layer 2 after the heat treatment. Of course, the underlayer 3 and the Sn alloy layer 2 may be formed directly on the surface of the base material 1 by plating or the like in this order without heat treatment. The underlayer 3 and the Sn alloy layer 2 can also be formed by vapor deposition, PVD, CVD, etc., in addition to wet plating.
When aluminum or aluminum alloy foil is used as the base material, a zinc substitution plating layer may be formed between the base layer 3 and the base material 1 as the base plating for electroplating the base layer 3.
　Ｓｎ合金層の表面にＳｎ酸化物が形成されていると好ましい。Ｓｎ酸化物は耐食性が高く、Ｓｎ合金層の表面にＳｎ酸化物が存在すると、Ｓｎ合金層の耐食性がさらに向上する。
　なお、図１（ａ）に示すように、加熱によりＳｎ合金層を形成する場合、Ｓｎからなる第２層２２を形成したときに自然酸化でＳｎ酸化物が第２層２２に形成され、その後の加熱による合金化によってもＳｎ合金層中に残存する。このＳｎ酸化物は、耐食性といった特性を向上させる効果がある。
　Ｓｎ酸化物は、層となっていなくてもよく、Ｓｎ合金層の表面に存在すればよいが、２～３０ｎｍの厚みとすると好ましい。Ｓｎ酸化物はＳｎ合金層と比較すると接触抵抗が高いため、層の厚みが３０ｎｍを超えると接触抵抗が増加する。
　なお、Ｓｎ合金層を熱処理によって形成した場合、熱処理の際に厚いＳｎ酸化物層が積極的に形成されるので好ましい。 It is preferable that Sn oxide is formed on the surface of the Sn alloy layer. Sn oxide has high corrosion resistance. When Sn oxide is present on the surface of the Sn alloy layer, the corrosion resistance of the Sn alloy layer is further improved.
As shown in FIG. 1A, when the Sn alloy layer is formed by heating, Sn oxide is formed in the second layer 22 by natural oxidation when the second layer 22 made of Sn is formed, and thereafter Even in the alloying by heating, the Sn alloy layer remains. This Sn oxide has an effect of improving characteristics such as corrosion resistance.
The Sn oxide does not have to be a layer and may be present on the surface of the Sn alloy layer, but a thickness of 2 to 30 nm is preferable. Since the Sn oxide has a higher contact resistance than the Sn alloy layer, the contact resistance increases when the thickness of the layer exceeds 30 nm.
Note that it is preferable to form the Sn alloy layer by heat treatment because a thick Sn oxide layer is positively formed during the heat treatment.
　次に、図３を参照し、本発明の実施の形態に係る電磁波シールド材１００について説明する。電磁波シールド材１００は電磁波シールド用金属箔１０と、この金属箔１０の片面に樹脂層又は樹脂フィルム４とを積層してなる。
　樹脂層としては例えばポリイミド等の樹脂を用いることができ、樹脂フィルムとしては例えばＰＥＴ(ポリエチレンテレフタラート)、ＰＥＮ（ポリエチレンナフタレート）のフィルムを用いることができる。樹脂層や樹脂フィルムは、接着剤により金属箔に接着されてもよいが、接着剤を用いずに溶融樹脂を金属箔上にキャスティングしたり、フィルムを金属箔に熱圧着させてもよい。又、樹脂フィルムにＰＶＤやＣＶＤで直接銅やアルミニウムの層を基材として形成したフィルムや、樹脂フィルムにＰＶＤやＣＶＤで銅やアルミニウムの薄い層を導電層として形成した後、この導電層上に湿式めっきで金属層を厚く形成したメタライズドフィルムを用いてもよい。
　樹脂層や樹脂フィルムとしては公知のものを用いることができる。樹脂層や樹脂フィルムの厚みは特に制限されないが、例えば１～１００μｍ、より好ましくは３～５０μｍのものを好適に用いることができる。又、接着剤を用いた場合、接着層の厚みは例えば１０μｍ以下とすることができる。
　材料の軽薄化の観点から、電磁波シールド材１００の厚みは１．０ｍｍ以下、より好ましくは０．０１～０．５ｍｍであることが好ましい。
　そして、電磁波シールド材１００をケーブルの外側に巻くことで、シールドケーブルが得られる。 Next, the electromagnetic shielding material 100 according to the embodiment of the present invention will be described with reference to FIG. The electromagnetic shielding material 100 is formed by laminating an electromagnetic shielding metal foil 10 and a resin layer or a resin film 4 on one surface of the metal foil 10.
For example, a resin such as polyimide can be used as the resin layer, and a film of PET (polyethylene terephthalate) or PEN (polyethylene naphthalate) can be used as the resin film. The resin layer and the resin film may be bonded to the metal foil with an adhesive, but the molten resin may be cast on the metal foil without using the adhesive, or the film may be thermocompression bonded to the metal foil. In addition, a film in which a copper or aluminum layer is directly formed on a resin film by PVD or CVD, or a thin layer of copper or aluminum is formed on a resin film by PVD or CVD as a conductive layer. You may use the metallized film which formed the metal layer thickly by wet plating.
A well-known thing can be used as a resin layer or a resin film. The thickness of the resin layer or the resin film is not particularly limited, but a resin layer having a thickness of, for example, 1 to 100 μm, more preferably 3 to 50 μm can be suitably used. When an adhesive is used, the thickness of the adhesive layer can be set to 10 μm or less, for example.
From the viewpoint of reducing the thickness of the material, the thickness of the electromagnetic shielding material 100 is preferably 1.0 mm or less, more preferably 0.01 to 0.5 mm.
And a shielded cable is obtained by winding the electromagnetic wave shielding material 100 around the outside of the cable.
　次に、実施例を挙げて本発明をさらに詳細に説明するが、本発明はこれらに限定されるものではない。
（基材）
　圧延銅箔としては、厚さ８μｍの圧延銅箔（ＪＸ日鉱日石金属製の型番Ｃ１１００）を用いた。
　電解銅箔としては、厚さ８μｍの無粗化処理の電解銅箔（ＪＸ日鉱日石金属製の型番ＪＴＣ箔）を用いた。
　Ｃｕメタライズドフィルムとしては、厚さ８μｍのメタライジングＣＣＬ（日鉱金属製の製品名「マキナス」）を用いた。
　アルミニウム箔としては、厚さ１２μｍのアルミニウム箔（サン・アルミニウム工業社製）を用いた。
　Ａｌメタライズドフィルムとしては、厚さ１２μｍのＰＥＴフィルム（東洋紡績社製）に真空蒸着でアルミニウムを６μｍ形成したものを用いた。 EXAMPLES Next, although an Example is given and this invention is demonstrated further in detail, this invention is not limited to these.
(Base material)
As the rolled copper foil, a rolled copper foil having a thickness of 8 μm (model number C1100 made by JX Nippon Mining & Metals) was used.
As the electrolytic copper foil, a non-roughened electrolytic copper foil having a thickness of 8 μm (model number JTC foil made by JX Nippon Mining & Metals) was used.
As the Cu metallized film, a metalizing CCL having a thickness of 8 μm (product name “Makinas” manufactured by Nikko Metal) was used.
As the aluminum foil, a 12 μm thick aluminum foil (manufactured by Sun Aluminum Industry Co., Ltd.) was used.
As the Al metallized film, a 12 μm-thick PET film (manufactured by Toyobo Co., Ltd.) with 6 μm of aluminum formed by vacuum deposition was used.
(Ｓｎ合金層)
　Ｓｎ合金層を、上記基材の片面に形成した。表１に、Ｓｎ合金層の形成方法を示す。
　表１において「めっき」とは、図１（ａ）に示す方法で第１層２１、第２層２２をこの順でめっきした後、窒素雰囲気下において１５０～１８０℃で２～７時間熱処理したものであり、熱処理後に第１層２１が残存した場合、その層を下地層として表１に組成を記載した。表１において「めっきのみ」とはめっきによりＳｎ層を形成し、熱処理を行わなかったものである。表１において「合金めっき」は、合金めっきによりＳｎ合金層を形成したものであり、合金めっきの前に基材上に下地層をめっきした。
　又、実施例１６～２０は、基材の片面に、表１に示すＮｉ合金めっきを下地層として形成した後、下地層の上にＳｎめっきを施し、さらに上記条件の熱処理によりＳｎ合金層を形成した。このとき下地層からＮｉ以外の元素（Ｐ、Ｗ、Ｆｅ、Ｃｏ）も拡散し、３成分を含むＳｎ合金層が形成された。
　又、実施例１１、１２、２０はアルミニウム箔に置換めっきによってＺｎ層を形成した後、Ｚｎ層の上に下地Ｎｉ層、下地Ｎｉ層の上にＳｎめっきを施し、さらに熱処理によりＳｎ合金層を形成した。このうち、Ｎｉ層の厚みを薄くした実施例２０の場合、表面のＳｎ層にＺｎ層からＺｎも拡散し、３成分を含むＳｎ－Ｎｉ－Ｚｎ合金層が形成された。
　又、比較例８はアルミニウム箔に置換めっきによってＺｎ層を形成した後、Ｚｎ層の上に下地Ｎｉ層をめっきし、下地Ｎｉ層の上にＳｎめっきを施した。 (Sn alloy layer)
An Sn alloy layer was formed on one side of the substrate. Table 1 shows a method for forming the Sn alloy layer.
In Table 1, “plating” means that the first layer 21 and the second layer 22 were plated in this order by the method shown in FIG. 1A and then heat-treated at 150 to 180 ° C. for 2 to 7 hours in a nitrogen atmosphere. When the first layer 21 remained after the heat treatment, the composition is shown in Table 1 with the layer as an underlayer. In Table 1, “Plating only” means that an Sn layer was formed by plating and no heat treatment was performed. In Table 1, “alloy plating” is the one in which an Sn alloy layer was formed by alloy plating, and the base layer was plated on the substrate before alloy plating.
In Examples 16 to 20, the Ni alloy plating shown in Table 1 was formed as an underlayer on one side of the base material, and then Sn plating was performed on the underlayer. Further, the Sn alloy layer was formed by heat treatment under the above conditions. Formed. At this time, elements other than Ni (P, W, Fe, Co) were also diffused from the base layer, and an Sn alloy layer containing three components was formed.
In Examples 11, 12, and 20, after forming a Zn layer on the aluminum foil by displacement plating, a base Ni layer is formed on the Zn layer, a Sn plating is applied on the base Ni layer, and a Sn alloy layer is further formed by heat treatment. Formed. Among them, in Example 20 in which the thickness of the Ni layer was reduced, Zn was also diffused from the Zn layer into the Sn layer on the surface, and a Sn—Ni—Zn alloy layer containing three components was formed.
In Comparative Example 8, after a Zn layer was formed on the aluminum foil by displacement plating, a base Ni layer was plated on the Zn layer, and Sn plating was applied on the base Ni layer.
　なお、各めっきは、以下の条件で形成した。
　　Ｎｉめっき：硫酸Ｎｉ浴（Ｎｉ濃度：２０ｇ／Ｌ、電流密度：２～１０Ａ／ｄｍ２）
　　Ｓｎめっき：フェノールスルホン酸Ｓｎ浴（Ｓｎ濃度：４０ｇ／Ｌ、電流密度：２～１０Ａ／ｄｍ２）
　　Ａｇめっき：シアン化Ａｇ浴（Ａｇ濃度：１０ｇ／Ｌ、電流密度：０．２～４Ａ／ｄｍ２）
　　Ｃｕめっき：硫酸Ｃｕ浴（Ｃｕ濃度：２０ｇ／Ｌ、電流密度：２～１０Ａ／ｄｍ２）
　　Ｚｎ置換めっき：ジンケート浴（Ｚｎ濃度：１５ｇ／Ｌ）
　　Ｎｉ－Ｓｎめっき：ピロリン酸塩浴（Ｎｉ濃度１０ｇ／Ｌ、Ｓｎ濃度１０ｇ／Ｌ、電流密度：０．１～２Ａ／ｄｍ２）
　　Ｃｏ－Ｓｎめっき：ピロリン酸塩浴（Ｃｏ濃度２０ｇ／Ｌ、Ｓｎ濃度２０ｇ／Ｌ、電流密度：０．２～３Ａ／ｄｍ２） Each plating was formed under the following conditions.
Ni plating: Ni sulfate bath (Ni concentration: 20 g / L, current density: 2 to 10 A / dm 2 )
Sn plating: phenol sulfonic acid Sn bath (Sn concentration: 40 g / L, current density: 2 to 10 A / dm 2 )
Ag plating: cyanide Ag bath (Ag concentration: 10 g / L, current density: 0.2 to 4 A / dm 2 )
Cu plating: Cu sulfate bath (Cu concentration: 20 g / L, current density: 2 to 10 A / dm 2 )
Zn displacement plating: zincate bath (Zn concentration: 15 g / L)
Ni—Sn plating: pyrophosphate bath (Ni concentration 10 g / L, Sn concentration 10 g / L, current density: 0.1 to 2 A / dm 2 )
Co—Sn plating: pyrophosphate bath (Co concentration 20 g / L, Sn concentration 20 g / L, current density: 0.2 to 3 A / dm 2 )
　　Ｎｉ－Ｐ：硫酸浴（Ｎｉ濃度：２０ｇ／Ｌ、Ｐ濃度：２０ｇ／Ｌ、電流密度：２～４Ａ／ｄｍ２）
　　Ｎｉ－Ｗ：硫酸浴（Ｎｉ濃度：２０ｇ／Ｌ、Ｗ濃度：２０ｇ／Ｌ、電流密度：０．１～２Ａ／ｄｍ２）
　　Ｎｉ－Ｆｅ：硫酸浴（Ｎｉ濃度：２０ｇ／Ｌ、Ｆｅ濃度：１０ｇ／Ｌ、電流密度：０．１～２Ａ／ｄｍ２）
　　Ｎｉ－Ｃｏ：硫酸浴（Ｎｉ濃度：２０ｇ／Ｌ、Ｃｏ濃度：１０ｇ／Ｌ、電流密度：０．１～２Ａ／ｄｍ２） Ni-P: sulfuric acid bath (Ni concentration: 20 g / L, P concentration: 20 g / L, current density: 2-4 A / dm 2 )
Ni—W: sulfuric acid bath (Ni concentration: 20 g / L, W concentration: 20 g / L, current density: 0.1 to 2 A / dm 2 )
Ni—Fe: sulfuric acid bath (Ni concentration: 20 g / L, Fe concentration: 10 g / L, current density: 0.1 to 2 A / dm 2 )
Ni—Co: sulfuric acid bath (Ni concentration: 20 g / L, Co concentration: 10 g / L, current density: 0.1 to 2 A / dm 2 )
　表１において「スパッタ」は、Ｎｉ，Ｓｎをこの順でスパッタした後、熱処理したものである。
　表１において「合金スパッタ」は、対応する合金のターゲット材を用いてスパッタして合金層を形成したものである。なお、合金スパッタで成膜される層は合金層そのものの組成であるので、熱処理は行わなかった。
　なお、スパッタ、合金スパッタは以下の条件で行った。
　　スパッタ装置：バッチ式スパッタリング装置（アルバック社、型式ＭＮＳ－６０００）
　　スパッタ条件：到達真空度１．０×１０-5Ｐａ、スパッタリング圧０．２Ｐａ、スパッタリング電力５０Ｗ
　　ターゲット：Ｎｉ（純度３Ｎ）、Ａｇ（純度３Ｎ）、Ｎｉ－Ｓｎ（それぞれ(質量％で)Ｎｉ：Ｓｎ＝８５：１５、８０：２０、５７：４３、４０：６０、２７：７３、２０：８０） In Table 1, “Sputtering” is a heat treatment after sputtering of Ni and Sn in this order.
In Table 1, “alloy sputtering” is an alloy layer formed by sputtering using a target material of a corresponding alloy. In addition, since the layer formed by alloy sputtering has the composition of the alloy layer itself, no heat treatment was performed.
Sputtering and alloy sputtering were performed under the following conditions.
Sputtering equipment: Batch type sputtering equipment (ULVAC, Model MNS-6000)
Sputtering conditions: ultimate vacuum 1.0 × 10 −5 Pa, sputtering pressure 0.2 Pa, sputtering power 50 W
Target: Ni (purity 3N), Ag (purity 3N), Ni-Sn (in mass%) Ni: Sn = 85: 15, 80:20, 57:43, 40:60, 27:73, 20: 80)
　表１において「蒸着」は、以下の条件で行った。
　　蒸着装置：真空蒸着装置（アルバック社、型式ＭＢ０５－１００６）
　　蒸着条件：到達真空度５．０×１０-３Ｐａ、電子ビーム加速電圧６ｋＶ
　　蒸着源：Ｎｉ（純度３Ｎ） In Table 1, “deposition” was performed under the following conditions.
Vapor deposition equipment: Vacuum vapor deposition equipment (ULVAC, model MB05-1006)
Deposition conditions: ultimate vacuum 5.0 × 10 −3 Pa, electron beam acceleration voltage 6 kV
Deposition source: Ni (purity 3N)
（Ｓｎ合金層、下地層、Ｓｎ酸化物層の同定及び厚みの測定）
　得られた電磁波シールド用金属箔の断面試料について、ＳＴＥＭ（走査透過型電子顕微鏡、日本電子株式会社製ＪＥＭ－２１００Ｆ）による線分析を行い、層構成を判定した。分析した指定元素は、Ｓｎ、Ａｇ、Ｎｉ、Ｃｕ、Ｐ、Ｗ、Ｆｅ、Ｃｏ、Ｚｎ、Ｃ、Ｓ及びＯである。また、上記した指定元素の合計を１００％として、各層における各元素の割合(ｗｔ％)を分析した（加速電圧：２００ｋＶ、測定間隔：２ｎｍ）。
　図４に示すように、Ｓｎを５ｗｔ％以上含み、かつＡｇ、ＮｉおよびＣｕのいずれかの元素を５ｗｔ％以上含む層をＳｎ合金層とし、その厚みを図４上（線分析の走査距離に対応）で求めた。Ｓｎ合金層よりも下層側に位置し、Ｓｎが５ｗｔ％未満であり、Ａｇ、ＮｉおよびＣｕのいずれかの元素を５ｗｔ％以上含む層を下地層とし、その厚みを図上で求めた。Ｓｎ合金層より上層側に位置し、Ｓｎが５ｗｔ％以上であり、かつＯが５ｗｔ％以上である層をＳｎ酸化物層とし、その厚みを図上で求めた。ＳＴＥＭの測定を３視野で行い、３視野×５カ所の平均値を各層の厚さとした。 (Identification of Sn alloy layer, underlayer, Sn oxide layer and measurement of thickness)
The cross-sectional sample of the obtained metal foil for electromagnetic wave shielding was subjected to line analysis by STEM (scanning transmission electron microscope, JEM-2100F manufactured by JEOL Ltd.) to determine the layer configuration. The analyzed designated elements are Sn, Ag, Ni, Cu, P, W, Fe, Co, Zn, C, S and O. Further, the ratio (wt%) of each element in each layer was analyzed with the total of the specified elements described above being 100% (acceleration voltage: 200 kV, measurement interval: 2 nm).
As shown in FIG. 4, a layer containing 5 wt% or more of Sn and containing 5 wt% or more of any element of Ag, Ni, and Cu is an Sn alloy layer, and the thickness is shown in FIG. Response). A layer that is located on the lower layer side of the Sn alloy layer and has Sn of less than 5 wt% and containing any element of Ag, Ni, and Cu in an amount of 5 wt% or more was used as a base layer, and the thickness thereof was determined on the drawing. The layer located on the upper layer side from the Sn alloy layer and having Sn of 5 wt% or more and O of 5 wt% or more was defined as an Sn oxide layer, and the thickness thereof was determined on the drawing. The STEM measurement was performed in 3 fields of view, and the average value of 3 fields × 5 locations was defined as the thickness of each layer.
（Ｓｎ合金層、下地層の組成）
　Ｓｎ合金層、下地層の組成は、ＳＴＥＭ（走査透過型電子顕微鏡）による線分析によって求めた。Ｓｎ合金層および下地層を構成する各元素を指定元素とし、指定元素の合計を１００％としたときの各元素の質量割合をＳｎ合金層、下地層の組成とした。
（硬さの測定）
　得られた電磁波シールド用金属箔のＳｎ合金層側の面について、ＩＳＯ１４５７７－１に従う、超微小押し込み硬さ試験で硬さを測定した。硬さの測定にはエリオニクス社製のＥＮＴ－２１００を使用した。 (Composition of Sn alloy layer and underlayer)
The composition of the Sn alloy layer and the underlayer was determined by line analysis using STEM (scanning transmission electron microscope). The elements constituting the Sn alloy layer and the underlayer were designated elements, and the mass ratio of each element when the total of the designated elements was 100% was defined as the composition of the Sn alloy layer and the underlayer.
(Measurement of hardness)
The surface of the obtained metal foil for electromagnetic wave shielding on the Sn alloy layer side was measured for hardness by an ultra-fine indentation hardness test in accordance with ISO14577-1. ENT-2100 made by Elionix was used for the measurement of hardness.
（接触抵抗及び耐食性の評価）
　得られた電磁波シールド用金属箔の合金層側の面について塩水噴霧試験を行い、試験前後のＳｎ合金層側の最表面の接触抵抗を測定した。
　接触抵抗の測定は山崎精機株式会社製の電気接点シミュレーターＣＲＳ－１を使用して四端子法で測定した。プローブ：金プローブ、接触荷重：２０ｇｆ、バイアス電流：１０ｍＡ、摺動距離：１ｍｍ
　塩水噴霧試験は、ＪＩＳ－Ｚ２３７１（温度:３５℃、塩水成分：塩化ナトリウム、塩水濃度：５ｗｔ％、噴霧圧力：９８±１０ｋＰａ、噴霧時間：４８ｈ）に従った。塩水噴霧試験前後の評価が共に◎か○であれば実用上、問題はない。なお、塩水噴霧試験前の初期の接触抵抗は、接触抵抗自体の評価を示し、塩水噴霧試験後の接触抵抗は耐食性の評価を示す。
　◎：接触抵抗が２０ｍΩ未満
　○：接触抵抗が２０ｍΩ以上、１００ｍΩ未満
　×：接触抵抗が１００ｍΩ以上 (Evaluation of contact resistance and corrosion resistance)
The surface on the alloy layer side of the obtained metal foil for electromagnetic shielding was subjected to a salt spray test, and the contact resistance of the outermost surface on the Sn alloy layer side before and after the test was measured.
The contact resistance was measured by a four-terminal method using an electrical contact simulator CRS-1 manufactured by Yamazaki Seiki Co., Ltd. Probe: gold probe, contact load: 20 gf, bias current: 10 mA, sliding distance: 1 mm
The salt spray test was in accordance with JIS-Z2371 (temperature: 35 ° C., salt water component: sodium chloride, salt water concentration: 5 wt%, spray pressure: 98 ± 10 kPa, spray time: 48 h). If the evaluation before and after the salt spray test is ◎ or か, there is no practical problem. The initial contact resistance before the salt spray test indicates the evaluation of the contact resistance itself, and the contact resistance after the salt spray test indicates the evaluation of corrosion resistance.
◎: Contact resistance is less than 20 mΩ ○: Contact resistance is 20 mΩ or more, less than 100 mΩ ×: Contact resistance is 100 mΩ or more
（Ｓｎカス）
　図６に示す試験装置３００を用いて評価した。
　得られた電磁波シールド用金属箔１０を、Ｓｎ合金層側の面が上になるように鉄板３０２上に貼り付け、その上に、ＢＷＦ(ドイツ)社製の厚み３ｍｍのＢＣフェルト（商品名）３０４を巻きつけた４．８ｍｍ径の鉄球３０６を組み込んだ錘３０８を置き、鉄球３０６に３０ｇの荷重を加えて往復距離１０ｍｍ、往復回数１５回で平面方向にＳｎ合金層上を擦った後、フェルト３０４に付着しためっきカスを目視で観察した。
　○：めっきカスが確認できない
　×：めっきカスが確認できた (Sn Cus)
Evaluation was performed using a test apparatus 300 shown in FIG.
The obtained metal foil 10 for electromagnetic wave shielding was affixed on the iron plate 302 so that the surface on the Sn alloy layer side was up, and a BC felt (trade name) manufactured by BWF (Germany) with a thickness of 3 mm. A weight 308 incorporating a steel ball 306 with a diameter of 4.8 mm around which 304 is wound was placed, and a load of 30 g was applied to the iron ball 306, and the Sn alloy layer was rubbed in the plane direction at a round trip distance of 10 mm and a round trip count of 15 times. Thereafter, the plating residue adhering to the felt 304 was visually observed.
○: No plating residue was confirmed ×: Plated residue was confirmed
　得られた結果を表１に示す。 The results obtained are shown in Table 1.
Figure JPOXMLDOC01-appb-T000001
Figure JPOXMLDOC01-appb-T000001
　表１から明らかなように、基材の表面に、Ｃｕ、Ｎｉ又はＡｇとＳｎとからなり、Ｓｎを２０～８０質量％含み、かつ厚さが３０～１５００ｎｍであるＳｎ合金層を有する各実施例の場合、接触抵抗が低く、耐食性に優れ、かつＳｎカスが発生しにくいものとなった。
　特に、めっき後に熱処理してＳｎ合金層を形成したために、他の実施例よりもＳｎ酸化物層が厚い実施例１～１２、１６～２０の場合、耐食性がさらに優れていた。
　なお、図４、５は、それぞれ実施例１の試料のＳＴＥＭによる断面像、及びＳＴＥＭによる線分析の結果を示す。断面像におけるＸ層、Ｙ層は、線分析の結果から、それぞれＮｉ－Ｓｎ合金層（Ｓｎ合金層）、Ｎｉ層（下地層）であることがわかる。 As is apparent from Table 1, each of the examples has an Sn alloy layer comprising Cu, Ni or Ag and Sn on the surface of the base material, containing 20 to 80% by mass of Sn and having a thickness of 30 to 1500 nm. In the case of the example, the contact resistance was low, the corrosion resistance was excellent, and Sn residue was hardly generated.
In particular, since the Sn alloy layer was formed by heat treatment after plating, the corrosion resistance was more excellent in Examples 1 to 12 and 16 to 20 where the Sn oxide layer was thicker than the other examples.
4 and 5 show a cross-sectional image of the sample of Example 1 by STEM and the result of line analysis by STEM, respectively. The X layer and Y layer in the cross-sectional image are found to be a Ni—Sn alloy layer (Sn alloy layer) and a Ni layer (underlayer) from the results of the line analysis, respectively.
　一方、Ｓｎ合金層を形成しなかった比較例１、２の場合、耐食性が大幅に劣った。
　Ｓｎ合金層の厚さが２０ｎｍ未満である比較例３の場合、耐食性が大幅に劣った。Ｓｎ合金層の厚さが１５００ｎｍを超えた比較例４の場合、Ｓｎカスは発生し難かったが、耐食性が大幅に劣った。なお、比較例４の塩水噴霧試験後の表面のＳｎ合金層をＳＥＭ（倍率５０００倍）で観察したところ、クラックが生じて基材が露出したのが観察された。
　Ｓｎ合金層として、Ｓｎ－Ｃｏ層を形成した比較例５の場合、Ｓｎカスは発生し難かったが、接触抵抗が高くなり、耐食性も劣った。
　Ｓｎ合金層の代わりに純Ｓｎ層を設けた比較例６～８の場合、Ｓｎ層の硬さが５００ＭＰａ以下となり、Ｓｎカスが顕著に発生した。
　Ｓｎ合金層の代わりにＮｉ層を形成した比較例９の場合、耐食性が劣った。
　Ｓｎ合金層中のＳｎの割合が２０質量％未満である比較例１０の場合、接触抵抗が高くなり、耐食性も劣った。又、Ｓｎ合金層の硬さが５００ＭＰａ以下となり、Ｓｎカスが顕著に発生した。
　Ｓｎ合金層の硬さが２００００ＭＰａを超えた比較例１１の場合、Ｓｎ合金層が硬くなり過ぎ、耐食性が大幅に劣った。なお、比較例１１の塩水噴霧試験後の表面のＳｎ合金層をＳＥＭ（倍率５０００倍）で観察したころ、クラックが生じて基材が露出したのが観察された。 On the other hand, in the case of Comparative Examples 1 and 2 where no Sn alloy layer was formed, the corrosion resistance was significantly inferior.
In the case of Comparative Example 3 in which the thickness of the Sn alloy layer was less than 20 nm, the corrosion resistance was significantly inferior. In the case of Comparative Example 4 in which the thickness of the Sn alloy layer exceeded 1500 nm, Sn residue was hardly generated, but the corrosion resistance was significantly inferior. In addition, when the Sn alloy layer of the surface after the salt spray test of the comparative example 4 was observed by SEM (magnification 5000 times), it was observed that the crack produced and the base material was exposed.
In Comparative Example 5 in which the Sn—Co layer was formed as the Sn alloy layer, Sn debris was hardly generated, but the contact resistance was high and the corrosion resistance was poor.
In Comparative Examples 6 to 8 in which a pure Sn layer was provided instead of the Sn alloy layer, the Sn layer had a hardness of 500 MPa or less, and Sn residue was remarkably generated.
In the case of Comparative Example 9 in which the Ni layer was formed instead of the Sn alloy layer, the corrosion resistance was inferior.
In the case of Comparative Example 10 in which the Sn ratio in the Sn alloy layer was less than 20% by mass, the contact resistance was high and the corrosion resistance was inferior. Further, the Sn alloy layer had a hardness of 500 MPa or less, and Sn residue was remarkably generated.
In the case of Comparative Example 11 in which the hardness of the Sn alloy layer exceeded 20000 MPa, the Sn alloy layer became too hard and the corrosion resistance was significantly inferior. In addition, when the Sn alloy layer on the surface after the salt spray test of Comparative Example 11 was observed with SEM (magnification 5000 times), it was observed that cracks occurred and the base material was exposed.
　１　　金属箔
　２　　Ｓｎ合金層
　３　　下地層
　４　　樹脂層又は樹脂フィルム
　１０　　電磁波シールド用金属箔
　１００　　電磁波シールド材 DESCRIPTION OF SYMBOLS 1 Metal foil 2 Sn alloy layer 3 Underlayer 4 Resin layer or resin film 10 Electromagnetic shielding metal foil 100 Electromagnetic shielding material

Claims (9)

  1. 　厚さ１００μｍ以下の金属箔からなる基材の片面又は両面に、Ｃｕ、Ｎｉ又はＡｇとＳｎとからなるＳｎ合金層が形成され、
    　該Ｓｎ合金層は、Ｓｎを２０～８０質量％含み、かつ厚さが３０～１５００ｎｍである電磁波シールド用金属箔。     An Sn alloy layer made of Cu, Ni or Ag and Sn is formed on one or both sides of a base material made of a metal foil having a thickness of 100 μm or less,
    The Sn alloy layer is a metal foil for electromagnetic wave shielding, containing 20 to 80% by mass of Sn and having a thickness of 30 to 1500 nm.
  2. 　前記Ｓｎ合金層の微小押し込み硬さが５００ＭＰａを超える請求項１記載の電磁波シールド用金属箔 The metal foil for electromagnetic wave shielding according to claim 1, wherein the indentation hardness of the Sn alloy layer exceeds 500 MPa.
  3. 　前記Ｓｎ合金層がさらに、Ｐ、Ｗ、Ｆｅ、Ｃｏ及びＺｎの群から選ばれる１種以上の元素を含む請求項１又は２に記載の電磁波シールド用金属箔。 The metal foil for electromagnetic wave shielding according to claim 1 or 2, wherein the Sn alloy layer further contains one or more elements selected from the group consisting of P, W, Fe, Co, and Zn.
  4. 　前記Ｓｎ合金層と前記基材との間に、Ｃｕ、Ｎｉ若しくはＡｇからなる金属層、又はＣｕ、Ｎｉ若しくはＡｇと、Ｐ、Ｗ、Ｆｅ、Ｃｏ若しくはＺｎとからなる合金層によって構成される下地層が形成されている請求項１～３のいずれかに記載の電磁波シールド用金属箔。 Between the Sn alloy layer and the base material, a metal layer made of Cu, Ni or Ag, or an alloy layer made of Cu, Ni or Ag and P, W, Fe, Co or Zn. The electromagnetic foil shielding metal foil according to any one of claims 1 to 3, wherein a formation is formed.
  5. 　前記Ｓｎ合金層の表面に、Ｓｎ合金層の酸化物層が形成されている請求項１～４のいずれかに記載の電磁波シールド用金属箔。 The electromagnetic foil shielding metal foil according to any one of claims 1 to 4, wherein an Sn alloy layer oxide layer is formed on a surface of the Sn alloy layer.
  6. 　前記基材が金、銀、白金、ステンレス、鉄、ニッケル、亜鉛、銅、銅合金、アルミニウム、又はアルミニウム合金からなる請求項１～５のいずれかに記載の電磁波シールド用金属箔。 6. The electromagnetic foil shielding metal foil according to claim 1, wherein the substrate is made of gold, silver, platinum, stainless steel, iron, nickel, zinc, copper, a copper alloy, aluminum, or an aluminum alloy.
  7. 　請求項１～６のいずれかに記載の電磁波シールド用金属箔の片面に、樹脂層が積層されている電磁波シールド材。 An electromagnetic wave shielding material in which a resin layer is laminated on one side of the metal foil for electromagnetic wave shielding according to any one of claims 1 to 6.
  8. 　前記樹脂層は樹脂フィルムであることを特徴とする請求項７に記載の電磁波シールド材。 The electromagnetic wave shielding material according to claim 7, wherein the resin layer is a resin film.
  9. 　請求項７又は８に記載の電磁波シールド材でシールドされたシールドケーブル。
    　     A shielded cable shielded with the electromagnetic shielding material according to claim 7 or 8.
PCT/JP2014/064473 2014-05-30 2014-05-30 Metal foil for electromagnetic wave shielding, electromagnetic wave shielding member, and shielded cable WO2015181969A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
PCT/JP2014/064473 WO2015181969A1 (en) 2014-05-30 2014-05-30 Metal foil for electromagnetic wave shielding, electromagnetic wave shielding member, and shielded cable

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/JP2014/064473 WO2015181969A1 (en) 2014-05-30 2014-05-30 Metal foil for electromagnetic wave shielding, electromagnetic wave shielding member, and shielded cable

Publications (1)

Publication Number Publication Date
WO2015181969A1 true WO2015181969A1 (en) 2015-12-03

Family

ID=54698343

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2014/064473 WO2015181969A1 (en) 2014-05-30 2014-05-30 Metal foil for electromagnetic wave shielding, electromagnetic wave shielding member, and shielded cable

Country Status (1)

Country Link
WO (1) WO2015181969A1 (en)

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3069015U (en) * 1999-02-02 2000-05-30 帝人株式会社 Electromagnetic wave shielding material
JP2003201597A (en) * 2002-01-09 2003-07-18 Nippon Denkai Kk Copper foil, production method therefor and electromagnetic wave shield body obtained by using the copper foil
JP2008274417A (en) * 2007-03-30 2008-11-13 Nikko Kinzoku Kk Laminated copper foil and method of manufacturing the same
JP2011086786A (en) * 2009-10-16 2011-04-28 Bridgestone Corp Method of manufacturing light permeable electromagnetic shield material, and light permeable electromagnetic shield material
WO2013105520A1 (en) * 2012-01-13 2013-07-18 Jx日鉱日石金属株式会社 Copper-foil composite, formed body, and manufacturing method therefor
WO2013105265A1 (en) * 2012-01-13 2013-07-18 Jx日鉱日石金属株式会社 Copper foil composite, molded body, and method for producing same
WO2013105266A1 (en) * 2012-01-13 2013-07-18 Jx日鉱日石金属株式会社 Copper foil composite, molded body, and method for producing same
JP5497949B1 (en) * 2013-07-03 2014-05-21 Ｊｘ日鉱日石金属株式会社 Metal foil for electromagnetic wave shielding, electromagnetic wave shielding material and shielded cable

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3069015U (en) * 1999-02-02 2000-05-30 帝人株式会社 Electromagnetic wave shielding material
JP2003201597A (en) * 2002-01-09 2003-07-18 Nippon Denkai Kk Copper foil, production method therefor and electromagnetic wave shield body obtained by using the copper foil
JP2008274417A (en) * 2007-03-30 2008-11-13 Nikko Kinzoku Kk Laminated copper foil and method of manufacturing the same
JP2011086786A (en) * 2009-10-16 2011-04-28 Bridgestone Corp Method of manufacturing light permeable electromagnetic shield material, and light permeable electromagnetic shield material
WO2013105520A1 (en) * 2012-01-13 2013-07-18 Jx日鉱日石金属株式会社 Copper-foil composite, formed body, and manufacturing method therefor
WO2013105265A1 (en) * 2012-01-13 2013-07-18 Jx日鉱日石金属株式会社 Copper foil composite, molded body, and method for producing same
WO2013105266A1 (en) * 2012-01-13 2013-07-18 Jx日鉱日石金属株式会社 Copper foil composite, molded body, and method for producing same
JP5497949B1 (en) * 2013-07-03 2014-05-21 Ｊｘ日鉱日石金属株式会社 Metal foil for electromagnetic wave shielding, electromagnetic wave shielding material and shielded cable

Similar Documents

Publication Publication Date Title
JP5497949B1 (en) Metal foil for electromagnetic wave shielding, electromagnetic wave shielding material and shielded cable
JP5887305B2 (en) Metal foil for electromagnetic shielding, electromagnetic shielding material, and shielded cable
WO2017090638A1 (en) Tin-plated copper terminal material, terminal, and wire terminal part structure
JP5774061B2 (en) Metal foil for electromagnetic wave shielding, electromagnetic wave shielding material and shielded cable
JP2013231223A (en) Plated material and method for producing the same
WO2015181970A1 (en) Metal foil for electromagnetic wave shielding, electromagnetic wave shielding member, and shielded cable
TWI431170B (en) A glossy nickel plating material, an electronic component using a glossy nickel plating material, and a method of manufacturing a glossy nickel plating material
JP5534627B1 (en) Metal foil for electromagnetic wave shielding, electromagnetic wave shielding material and shielded cable
WO2018124115A1 (en) Surface treatment material and article fabricated using same
JP5619307B1 (en) Metal foil for electromagnetic wave shielding, electromagnetic wave shielding material and shielded cable
WO2014148201A1 (en) Silver-plated material
KR20130124383A (en) Rolled copper or copper-alloy foil provided with roughened surface
WO2015181969A1 (en) Metal foil for electromagnetic wave shielding, electromagnetic wave shielding member, and shielded cable
JP5534626B1 (en) Metal foil for electromagnetic wave shielding, electromagnetic wave shielding material and shielded cable
JP5887287B2 (en) Metal foil for electromagnetic shielding and electromagnetic shielding material
JP2008196010A (en) Plating material for connector terminal
JP5887283B2 (en) Metal foil for electromagnetic shielding and electromagnetic shielding material
JP2018016878A (en) Manufacturing method of tin plating copper terminal material
JP2021075772A (en) Material for electric contact, its manufacturing method, connector terminal, connector, and electronic component

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 14893327

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

NENP Non-entry into the national phase

Ref country code: JP

122 Ep: pct application non-entry in european phase

Ref document number: 14893327

Country of ref document: EP

Kind code of ref document: A1