Furukawa ElectricNewNew Products
Products

Resin-Coated Metal Strips “FCOAT”

1.

INTRODUCTION

As portable equipment acquires higher functionality and amore compact configuration, there has been a growing
need for slim-line mounted components, so that with theconventional metal case, it is difficult to maintain electricalinsulation between the elements inside. This creates aneed for materials that provide both magnetic shielding(metal) and electrical insulation (resin), and demand forthem is increasing.
FCOAT is a sheet-shaped product with a metal substrate coated with resin (Figure 1 and Figure 2). It wasdeveloped to meet the needs described above, uses anintegrated manufacturing process from copper alloy, andhas been mass-marketed for power amp modules, cam-Metal substrate(copper alloy, stainless steel etc.)

Insulating heatresistant resin (PAI)

Packageplating (Sn etc.)
Heat-resistant under
plating (Ni etc.)

Figure 1

Cross-sectional structure of FCOAT.

era modules and similar applications (Figure 3 and Figure4). Currently examples of usage are expanding rapidly,with emphasis on components inside mobile phones, andwe intend to extend product specifications, including plating specifications, in response to these various needs.

2.

FEATURES(1) Magnetic shielding: Use of metal substrates of copper alloy or stainless steel makes it optimal in shielded cases for high-frequency components.
(2) Stiffness and heat dissipation: Use of metal substrates of copper alloy or stainless steel makes possible much slimmer (low back) cases than with plastic,
and heat dissipation is outstanding.
(3) High insulating performance and heat resistance:
Coated with polyamide-imide resin having high electrical insulating performance. Polyamide-imide resin
offers resistance to higher temperatures, and maintains high resistance reliability even in high-temperature environments or for reflow mounting.
(4) High-accuracy stripe coating: Multiple resin stripes
can be formed with high accuracy, and resin can bemolded to conform to component configuration.
(5) Easy workability: Use of resin with outstanding
stretch and adhesion properties makes possible
Case

No clearance
obtainable
Internal elements

Full-surface coating
for better insulation

Figure 2

Appearance of FCOAT products

Figure 4

Figure 3

Coating the insulator

Gap left for better
heat dissipation

Schematic of FCOAT applications.

Applications of FCOAT for mobile phones.

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stamping of blanks with minute dimensions, as well
as bending, and other press forming operations.
(6) High-temperature mounting properties: Plating finishes with Ni/Sn layers are provided to cater to applications involving solder mounting, and externalmount plating with outstanding solder wetting properties is also possible. And with a view to accommodating even higher solder wetting properties andcontact point applications, we are in the process ofdeveloping plating finishes with Ni/Au layers.
(7) Low cost: Reduces process steps and lowers costs
compared to processes involving insertion or application of polyimide film.
(8) Quick delivery: It is possible to shorten prototype andmass-production delivery lead times when resin
dimensional specifications are changed.

3.

APPLICATIONSIn addition to the low-back type of high-frequency modular components, connector cases, and narrow-pitch connector cases, FCOAT is expected to be applicable in avariety of electronic equipment applications. It is extremely well suited in replacing or reducing the cost of the heretofore expensive process steps of film insertion or application, and to shortening delivery times when designchanges occur.
For more information, please contact:
No.1 Sales Division, Metals Company, Furukawa
Electric		 TEL: +81-3-3286-3866 FAX: +81-3-3286-3289
Kansai Metals Sales Division, Furukawa Electric		 TEL: +81-6-6346-4123 FAX: +81-6-6346-4195

PRODUCT SPECIFICATIONS

Table 1 shows representative FCOAT specifications. The
resin coating can be applied in high-accuracy stripes atthe desired position and in the desired number. The
scope of manufacture is scheduled to be expanded, andfurther inquiries regarding non-standard specifications
are encouraged.

4.

5.

PROPERTIES

Table 2 shows representative properties of FCOAT materials. Even when subjected to rigorous reliability testing,
FCOAT products maintained excellent resin properties
and workability, and high dielectric properties.
Figure 5 shows the dependence of dielectric breakdown voltage on polyamide-imide resin film thickness.
The resin has high voltage resistance and can also beused in connectors and similar applications. In applications requiring particularly stringent voltage resistanceproperties, multi-layer coatings and full-length voltageresistance inspection can also be provided, and further
inquiries are encouraged.

Table 2

Representative properties of FCOAT materials.

Nature of test

Item evaluatedResin type/thickness (μm)

Composition of material
testedProduct as is(neglecting accelerated
aging treatment)

Phosphor bronze, nickel silver, SUS, etc.

Thickness

0.1~0.35 mm

Width
Type of coating
Material
Thickness
Resin

6~50 mm
Partial- or full-surface, One- or two-side
Polyamide-imide
3~20 μm

Thickness accuracy≦±3 μm from center

Stripe dimensions

2~48 mm

No. of stripes

Multiple possible

Stripe position

Anywhere except edge

Positional accuracy
Material
Plating

Manufacturable scope

Item
Material

8 % phosphor
bronzeInsulation resistance (Ω)≧7.45×10○

Resin coating hardening (pencil hardness)

9H

Resin adhesion (press evaluation)○

Plating adhesion (crosscut test)○

Plating heat-resistance discoloration(150°C×2 h, 220°C×20 min)○Insulation resistance (Ω))(12Solder wettability (wet area evaluation)

Heat cycling-55°C, 30 min⇔125°C, 30 min,200 cycles11≧6.42×10

Resin adhesion (press evaluation))○12≧4.40×10

Resin adhesion (press evaluation)○12

Low-temperature exposure Insulation resistance (Ω)(-40°C, 1000 h)
Resin adhesion (press evaluation)≧1.00×10

High-temperature exposure Insulation resistance (Ω)(85°C, 1000 h)
Resin adhesion (press evaluation)≧1.27×10

Insulation resistance (Ω)
Humidity resistance(85°C, 85 % RH, 1000 h) Resin adhesion (press evaluation)≧1.62×10

Dielectric breakdown voltage (kVAC)

Strip

Representative FCOAT Specifications.

1 (Ni)/2 (Sn)Substrate

Insulation resistance (Ω)○14○14○10≧1.13×10

Insulation resistance (Ω)

Reflow resistance(270°C, 5 min×5)

Table 1

Plating thickness (μm)

PCT
121°C, 100 %RH,2 atm, 96 h(Result of evaluation
PAI/7

Resin adhesion (press evaluation)○864

200102030

40Film thickness (µm)

± 0.1~0.15 mm
Ni, Sn etc.

Primer layer thickness~2 μm

Finished thickness~10 μmFigure 5

Dependence of dielectric breakdown voltage on polyamide-imide resin film thickness.

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