Sil-Pad K-4
®
The Original Kapton
®
-Based Insulator
Features and Benefits
• Thermal impedance:
0.48°C-in
2
/W (@50 psi)
• Withstands high voltages
• High dielectric strength
• Very durable
PROPERTY
Color
Reinforcement Carrier
Thickness (inch) / (mm)
Hardness (Shore A)
Breaking Strength (lbs/inch) / (kN/m)
Elongation (%)
Tensile Strength (psi) / (MPa)
Continuous Use Temp (°F) / (°C)
ELECTRICAL
Dielectric Breakdown Voltage (Vac)
Dielectric Constant (1000 Hz)
Volume Resistivity (Ohm-meter)
Flame Rating
THERMAL
Thermal Conductivity (W/m-K)
TYPICAL PROPERTIES OF SIL-PAD K-4
IMPERIAL VALUE
Gray
Kapton
0.006
90
30
40
5000
-76 to 356
6000
5.0
10
12
METRIC VALUE
Gray
Kapton
0.152
90
5
40
34
-60 to 180
6000
5.0
10
12
TEST METHOD
Visual
—
ASTM D374
ASTM D2240
ASTM D1458
ASTM D412
ASTM D412
—
ASTM D149
ASTM D150
ASTM D257
U.L.94
ASTM D5470
VTM-O
0.9
10
3.66
1.07
25
VTM-O
0.9
50
3.13
0.48
Sil-Pad K-4 uses a specially developed film
which has high thermal conductivity, high
dielectric strength and is very durable. Sil-Pad
K-4 combines the thermal transfer properties
of well-known Sil-Pad rubber with the physical
properties of a film.
Sil-Pad K-4 is a durable insulator that with-
stands high voltages and requires no thermal
grease to transfer heat. Sil-Pad K-4 is available
in customized shapes and sizes.
THERMAL PERFORMANCE vs PRESSURE
Pressure (psi)
TO-220 Thermal Performance (°C/W)
Thermal Impedance (°C-in /W) (1)
2
100
2.74
0.42
200
2.42
0.38
3.43
0.68
1) The ASTM D5470 test fixture was used.The recorded value includes interfacial thermal resistance.These values are provided for
reference only. Actual application performance is directly related to the surface roughness, flatness and pressure applied.
Typical Applications Include:
• Power supplies
• Power semiconductors
• Motor controls
Configurations Available:
• Sheet form, die-cut parts and roll form
• With or without pressure sensitive adhesive
Building a Part Number
SPK4
–
0.006
– 00
– 12/250 –
NA
Standard Options
Section E
NA = Selected standard option. If not selecting a standard
option, insert company name, drawing number, and
revision level.
_ _ _ = Standard configuration dash number,
1212 = 12" x 12" sheets, 12/250 = 12" x 250' rolls, or
00 = custom configuration
AC = Adhesive, one side
00 = No adhesive
Standard thicknesses available: 0.006"
SPK4 = Sil-Pad K4 Material
Section A
Section B
Section C
Note: To build a part number, visit our website at www.bergquistcompany.com.
Sil-Pad
®
: U.S. Patents 4,574,879; 4,602,125; 4,602,678; 4,685,987; 4,842,911 and others.
Kapton
®
is a registered trademark of DuPont.
www.bergquistcompany.com
The Bergquist Company -
North American Headquarters
18930 West 78th Street
Chanhassen, MN 55317
Phone: 800-347-4572
Fax: 952-835-0430
The Bergquist Company -
European Headquarters
Bramenberg 9a, 3755 BT Eemnes
Netherlands
Phone: 31-35-5380684
Fax: 31-35-5380295
The Bergquist Company - Asia
Room 15, 8/F Wah Wai Industrial Centre
No. 38-40, Au Pui Wan Street
Fotan, Shatin, N.T. Hong Kong
Ph: 852.2690.9296
Fax: 852.2690.2344
All statements, technical information and recommendations herein are based on tests we believe to be reliable, and
THE FOLLOWING IS MADE IN LIEU OF ALL WARRANTIES, EXPRESSED OR IMPLIED, INCLUDING THE IMPLIED
WARRANTIES OF MARKETABILITY AND FITNESS FOR PURPOSE. Sellers’ and manufacturers’ only obligation shall be to
replace such quantity of the product proved to be defective. Before using, user shall determine the suitability of the product
for its intended use, and the user assumes all risks and liability whatsoever in connection therewith. NEITHER SELLER NOR
MANUFACTURER SHALL BE LIABLE EITHER IN TORT OR IN CONTRACT FOR ANY LOSS OR DAMAGE, DIRECT,
INCIDENTAL, OR CONSEQUENTIAL, INCLUDING LOSS OF PROFITS OR REVENUE ARISING OUT OF THE USE OR
THE INABILITY TO USE A PRODUCT. No statement, purchase order or recommendations by seller or purchaser not
contained herein shall have any force or effect unless in an agreement signed by the officers of the seller and manufacturer.
PDS_SP_K4_12.08
Section D
