F-CO TM Sheet

Furukawa Electric has recently developed and brought
into the marketplace "F-CO TM Sheet", a high-performance heat-conductive sheet that does not contain low
molecular-weight siloxane.
The F-CO TM Sheet can be used to obtain a significant
heat dissipation effect simply by inserting the sheet
between a heat-generating electronic component and its
cooling device.

1.

HEAT-CONDUCTIVE SHEET

Many components for electronic equipment of these days
tend to generate more heat accompanied by theirimprovement in performance, requiring heat-conductive
sheets as one of the heat-dissipating measures.
Conventional heat-conductive sheets were made of silicone materials mostly to provide good flexibility and highthermostability. These silicone materials, however, oftencaused problems such that low molecular-weight siloxane
contained in the material was volatilized due to the hightemperatures produced by heat-generating devices, subsequently adhering to the electrical contacts in the equipment such as motors, relays and switches, thereby producing silicon dioxide --an electrical insulator-- and eventually causing defective electrical contacts. Thus, it haslong been desired that a siloxane-free heat-conductive
sheet be developed that is provided with equivalent characteristics as for the silicone-based products in terms offlexibility and thermostability.
In response to such a requirement, Furukawa Electric
has developed and brought into the marketplace F-CO TM
Sheet, a non-silicone heat-conductive sheet, based mainlyon acrylic rubber. At this time, the company has developed new types of heat-conductive sheets that are provided with a variety of functions.

2.

TRENDS IN APPLICATION OF HEATCONDUCTIVE SHEETThe current situation with heat-conductive sheets is suchthat it is generally required to have not only higher heat
conductivity to enable more efficient heat dissipation but
also some functions other than heat conduction to add
more values to the products.

Photo 1

Appearance of F-CO TM Sheet.

2.1

Electromagnetic Interference (EMI) Suppression
Applications
Suppression of electromagnetic noise has become essential in many fields such as the next-generation mobile
phone system as well as the intelligent transport system(ITS) that has recently begun implementation, and it isclear that these fields are growing both in number and indiversity. Furthermore, the proliferation of digital equipment is now influencing electromagnetic environments athomes and in offices, thus raising calls for effective countermeasures as electronic equipment continue to develop.
Two methods are known as such countermeasures:electromagnetic wave shielding technology where reflection by shielding materials is used to block the electromagnetic noise generated; and electromagnetic wave
absorbing technology where electromagnetic noise isabsorbed and ultimately converted into heat. The EMI
suppression type of F-CO TM Sheet is based on the latter
technology.
2.2 High-adhesion Applications
Some digital equipment have grown in size recently. Insuch large-sized equipment, both of the heat-generatingand heat-dissipating devices are large in size accordingly,
necessitating closer contact between these devices toeffect higher heat dissipation. This results in a demand fora heat-conductive sheet of high-adhesion type that is to
be inserted between these devices.
In the case of compact equipment, on the other hand,
heat-conductive sheets are often used like a double-faced
tape without using fastening screws, thus requiring a heatconductive sheet of high-adhesion type.

12.3 Low-hardness Applications
In the case of compact electronic equipment, there is ademand for a very soft, i.e., low-hardness heat-conductive
sheet, in order to increase the area of close contact
between the heat-generating and heat-dissipating devices
to effect more efficient heat dissipation.

3.

PRODUCT TYPES AND FEATURES OF
F-CO TM SHEETSIn response to such trends described above, we have promoted the development of F-CO TM Sheet, so that thevarious types shown below are now available.

Features common among these types are as follow:
1) Stabilized heat conductivity
The products maintain, due to our proprietary technology of compounds, stabilized heat conductivity duringlong-term use.
2) Elimination of siloxane
As mentioned at the beginning, the products are constituted of non-silicone rubber thus completely elimiTable 1TypeProd

uct No.

IN CONCLUSION

Characteristics of F-CO TM Sheet.

Standard
2014

For more information, please contact:
Thermal Product Department, Electronics Component
Division
TEL: 0463-24-9784
FAX: 0463-24-9786
Research and Development Department, F-COCompany
TEL: 0463-21-4873
FAX: 0463-21-5509

Thin-film composite

High heat-conductivity
N-500

EE

Aluminum foil core

Double-faced

A90/20-2

A250/100-2

Thermal conductivity (W/mK)

1.6

1.6

2.5

1.4

1.4

Thermal resistance (°C/W)

0.57

0.31

0.50

0.13

0.31

Volume resistivity (Ω . cm)

1✕10122.7✕1012

1✕1012//

Dielectric strength (kV/mm)

202820//

Flame retardance by UL94

V–0/

V–0//

30 % Compression strength (N/cm2)

842780//Adhesion strength with Al (N/25 mm)

/

3.6/

1.5

6.5

EMI suppression

High-adhesion

Low-hardnessPZEPTypeProdItem

24.

We intend to promote hereafter the development of F-COTM Sheet in response to diversified customers' needs.
We are ready to offer our development proposals forany requirements concerning F-CO TM Sheet not coveredin the description presented above. So, please feel free tocontact the below mentioned.

• Standard type• High heat-conductivity type• Thin-film composite type• High withstand-voltage type• EMI suppression type• High-adhesion type
• Low-hardness type

Itemnating concern about contact failures caused byvolatilization of low molecular-weight siloxane.
3) Elimination of halogens
All types of F-CO TM Sheet do not contain any
halogenous materials that may emit toxic gases.
Regardless of this, certain types with high flame retardation are available.
Thus, all the products are environment-harmonizedeliminating halogens, so that customers can feel assured
in using them.

uct No.

High withstand-voltage
Single-faced

Double-faced

EN500/50-1

EN500/50-2

Thermal conductivity (W/mK)

1.6

1.6

2.0

0.6

1.1

Thermal resistance (°C/W)

0.35

0.28

0.55

1.2

0.8

Volume resistivity (Ω . cm)

2.5✕1011

3.9✕1011

1.0✕1010

8.0✕1014

2.4✕1014

Dielectric strength (kV/mm)

3533/32/

Flame retardance by UL94

HBHB

V–0

V–1

V–0

30 % Compression strength (N/cm2)

13010080/

10Adhesion strength with Al (N/25 mm)

2.8

3.0/10/

Furukawa Review, No. 222002