NewNew Products
Products

Resin Coated Metal Sheet, FCOAT®

1.

INTRODUCTION

The Metals Company of Furukawa Electric has brought
to the marketplace FCOAT® products, a series of resin
coated metal sheets for electromagnetic shielding casefor RF components in mobile phones and the like.
As mobile equipment improve in functionality andcompactness, the components mounted are required tobe low in profile, rendering it difficult to ensure electricalinsulation using conventional metal cases. Accordingly,
demands are growing for such materials that makeelectromagnetic shielding and electrical insulation
properties compatible, using metal and resin.
FCOAT sheet is a material that combines a metal
substrate and a resin film, developed in order to meetthe needs mentioned above. We have established acomprehensive production system including the basealloys and have promoted mass production targeting at
power amplifier modules and camera modules. Since theproduct is increasingly employed in various electronicequipment centering on mobile phones, we intend toexpand its varieties including plating specifications soas to meet various requirements. See Figures 1, 2 andPhotos 1, 2.
Metal substrate forelectromagnetic shielding
Heat-resistant resin
for insulation
Plating for mounting withimproved wettability (Sn)
Underplating for heat resistance (Ni)Figure 1

Structure of FCOAT.

Conventional method
Case

Lack of sufficient
clearance
Components

Use of FCOAT
Coating with insulating film
Sufficient insulation
with allover coating

Figure 2

Sufficient clearance for
improved heat dissipation

Schematic of FCOAT application.

Photo 1

Photo 22.

Appearance of FCOAT sheets.

Applications of FCOAT for mobile phones.

FEATURES(1) Electromagnetic Shielding Performance
Because FCOAT sheets use metallic substrates
including copper alloys and stainless steels, they are
best suited for electromagnetic shielding cases for RFcomponents.
(2) High Electrical Insulation and Heat Resistance
Polymer resins with high electrical resistance are usedin coating, including polyamideimide and polyimide
for high-temperature applications. Thus, high reliability
in electrical insulation is maintained even in harshenvironments and after reflow mounting.
(3) High-precision Stripe Coating and Heat Dissipation
The resin is coated in multiple striped films with highprecision, so that the sheet is applicable to mounting ofmultiple components, ensuring high heat dissipation aswell.
(4) High Formability
The resin has superior elongation and adhesivenessproperties, so that the sheet is suitable for press forming
such as precision stamping, bending and drawing.
(5) Heat-resistant Solderability
For solder-mounting, plating with superior wettability forsoldering is available including underplating finish withNi/Sn solder.
(6) Low Cost
Because FCOAT sheets are resin-coated products
without using expensive polyimide films and the like, they

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Resin Coated Metal Sheet, FCOAT®

3.

SPECIFICATIONS

Typical specifications of the products are shown in Table
1. Please contact us for other specifications not shown
here, since we intend to expand the manufacture range.
Table 1Resin film

PlatingSpecifications

Metal/AlloyCu-Sn-P (Phosphor bronze),
Cu-Ni-Zn (Nickel silver),
SUS (Stainless steel), etc.

Thickness

0.1 to 0.35 mm

Width

6 to 50 mm

Coating area

Striped or whole area

Resin

Polyamideimide, Polyimide,Epoxy, Polyester, etc.

Thickness

3 to 20 µm

Accuracy of thickness±3 µm from center

Coating width

2 to 48 mm

Number of stripes

About 2 to 3

Accuracy of position±0.1 to 0.2 mm

Material

Ni, Sn, etc.

Thickness of underplating~ 2 µmPROPERTIES

Table 2 shows the evaluation results of the propertiesof typical FCOAT resins. It can be seen that the resinsmaintain, after severe reliability tests, superior resin
properties, formability, wettability for soldering and highelectrical insulation. We recommend polyamideimide
for the coating resin from the standpoint of cost andprocessing reliability.
Figure 3 shows the relationship between the resin film
thickness and breakdown voltage. The resin has highwithstanding voltage, making FCOAT sheets applicable toconnectors.

Typical specifications of FCOAT sheets.
Construction

Basematerial4.

Breakdown voltage (kV, AC)enable shortening of working time as well as significant
cost reduction.
(7) Quick Delivery
Quick delivery of not only volume products but also
prototype products can be ensured, including theproducts of modified specifications with respect to thenumber, width and position of the striped coating.

864200102030

40Film thickness of polyamideimide (µm)

Figure 35.

Relationship between resin film thickness andbreakdown voltage.

APPLICATIONSIn the future, FCOAT sheets are expected to be
used in various electronic applications including RFcomponents and connectors in mobile phones as thedigital functionality ever upgrades. They are suitable forThickness of external plating ~ 10 µm

Table 2
Reliability tests

Comparison of the properties of typical FCOAT resins.

Evaluation items

Resin

Cost of resin (Relative)
Cost of product (Relative)
Resin thickness
Plating
Base alloy
Electrical resistivity (Ω)
Solderability
Pencil hardness of resin film
As manufactured
Resin adherence after forming
Plating adherence
Plating color change, 150 °C x 2 hr,
or 220 °C x 20 min
Electrical resistivity (Ω)
PCT exposure, 121 °C x 96 hr, 2 atm,
100%RH
Resin adherence after forming
Heat cycle, from –55 °C x 30 min to 125 °C x Electrical resistivity (Ω)
30 min, 200 cycle
Resin adherence after forming
Electrical resistivity (Ω)
Low-temperature exposure, –40 °C x 1000 hr
Resin adherence after forming
Electrical resistivity (Ω)
High-temperature exposure, 85 °C x 1000 hr
Resin adherence after forming
Electrical resistivity (Ω)
Humidity exposure, 85 °C x 1000 hr, 85%RH
Resin adherence after formingMaterial construction

Reflow resistance, 270 °C x 5 min, 5 cycle

Electrical resistivity (Ω)
Pencil hardness of resin film

Polyimide

Polyamideimide

Epoxy

10~30
1
11.2~1.8
1
1~1.2
8 µm
7 µm
7 µm
1 µm-Ni/2 µm-Sn
1 µm-Ni/2 µm-Sn
1 µm-Ni/2 µm-Sn
6%Sn-Phospor bronze 6%Sn-Phospor bronze 6%Sn-Phospor bronze≥2.63×1013≥7.45×1012≥7.91×1010
7H9H6H≥1.97×1013≥6.42×1011≥4.99×1010≥1.08×1014≥4.40×1012≥3.62×1010≥1.10×1014≥1.00×1012≥1.77×1010≥1.25×1014≥1.27×1014≥2.62×1011≥1.05×1014≥1.62×1014≥1.19×1010
6H≥1.13×1010
5H≥1.25×1010∆ (Crack in bent ortensioned outer layer)≥1.43×1010
9H

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Resin Coated Metal Sheet, FCOAT®

replacing the conventional processes of film insertion andattachment, thus reducing costs, and also for coping withmodel changes being supported by quick delivery.
For more information, please contact:
First Sales Dept., Metals Co.
TEL: +81-3-3286-3841
FAX: +81-3-3286-3289
Kansai Metals Sales Dept., Metals Co.
TEL: +81-6-6346-4123
FAX: +81-6-6346-4195

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