Typical technical information and properties of dielectric material for
flexible printed circuitry.
| Property |
 |
Units |
|
Polyimide |
|
Polymide
(Adhesiveless) |
|
Polyester |
|
|
|
|
|
|
|
|
| Representative Trade Name |
|
- |
|
Polyimide |
|
Polyimide |
|
Mylar |
|
|
|
|
|
|
|
| Physical |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Thickness Range |
|
mil |
|
.5 to 5 |
|
1 - 6 |
|
0.025 to .5 |
|
|
|
|
|
|
|
| Tensile Strength (at 25° C) |
|
psi |
|
25,000 |
|
50,000 |
|
20,000 to 35,000 |
|
|
|
|
|
|
|
| Break Elongation |
|
% |
|
70 |
|
50 |
|
60 to 165 |
|
|
|
|
|
|
|
| Tensile Modulus (at 25° C) |
|
100,000 psi |
|
4.3 |
|
.7 |
|
5 |
|
|
|
|
|
|
|
| Tear Initiation Strength |
|
lb/in |
|
1000 |
|
700 - 1200 |
|
1000 to 1500 |
|
|
|
|
|
|
|
| Tear Propagation Strength |
|
g/mil |
|
8 |
|
20 |
|
12 to 25 |
|
|
|
|
|
|
|
| Chemical |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Resistance to: |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Strong Acids |
|
- |
|
Good |
|
Good |
|
Good |
|
|
|
|
|
|
|
| Strong Alkalis |
|
- |
|
Poor |
|
Good |
|
Poor |
|
|
|
|
|
|
|
| Grease and Oil |
|
- |
|
Good |
|
Good |
|
Good |
|
|
|
|
|
|
|
| Organic Solvents |
|
- |
|
Good |
|
Good |
|
Good |
|
|
|
|
|
|
|
| Water |
|
- |
|
Good |
|
Good |
|
Good |
|
|
|
|
|
|
|
| Sunlight |
|
- |
|
Fair |
|
Good |
|
Good |
|
|
|
|
|
|
|
| Fungus |
|
- |
|
Non-nutrient |
|
Non-nutrient |
|
Non-nutrient |
|
|
|
|
|
|
|
| Water Absorption (ASTM D570) |
|
% (24 hours) |
|
2.9 |
|
.8 |
|
<0.8 |
|
|
|
|
|
|
|
| Thermal |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Service Temperature (min/max)
Coefficient of Thermal |
|
degree C |
|
-200/+300 |
|
-200/ +350 |
|
-60/+105 |
|
|
|
|
|
|
|
| Expansion (at 22° C) |
|
PPM/ degree C |
|
20 |
|
20 |
|
27 |
|
|
|
|
|
|
|
Change in Linear Dimensions
(100° C, 30 min) |
|
% |
|
<0.3 |
|
0.01 - 0.02 |
|
<0.5 |
|
|
|
|
|
|
|
| Electrical |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Dielectric Constant (ASTM D150)
1MHz |
|
|
|
3.4 |
|
3.4 |
|
3 |
|
|
|
|
|
|
|
Dissipation Factor (ASTM D150)
1MHz |
|
|
|
0.01 |
|
.003 |
|
0.018 |
|
|
|
|
|
|
|
Dielectric Strength (ASTM D149)
@ 5 mil thickness
Volume Resistivity (ASTM D257) |
|
V/mil
ohm-cm |
|
3800
1.0E+16 |
|
6000
1.0E+16 |
|
3400
1.0E+16 |
Current Carrying Capabilities:
|
Copper Weight |
| AMPS |
1/2 oz. (0.0007") |
1 oz.
(0.0014") |
2 oz. (0.0028") |
3 oz. |
4 oz. |
5 oz. |
6 oz. |
7 oz. |
|
Width in Inches |
| 0.5 |
0.013" |
0.008" |
N/A |
N/A |
N/A |
N/A |
N/A |
N/A |
| 1.0 |
0.028" |
0.017" |
0.013" |
N/A |
N/A |
N/A |
N/A |
N/A |
| 1.5 |
0.040" |
0.027" |
0.020" |
N/A |
N/A |
N/A |
N/A |
N/A |
| 2.0 |
0.053" |
0.040" |
0.030" |
0.0235" |
N/A |
N/A |
N/A |
N/A |
| 2.5 |
0.080" |
0.060" |
0.042" |
0.0325" |
0.0285" |
N/A |
N/A |
N/A |
| 3.0 |
0.100" |
0.083" |
0.057" |
0.045" |
0.0387" |
N/A |
N/A |
N/A |
| 4.0 |
0.160" |
0.120" |
0.088" |
0.066" |
0.055" |
0.048" |
0.043" |
N/A |
| 5.0 |
0.225" |
0.158" |
0.118" |
0.09" |
0.074" |
0.065" |
0.059" |
0.053" |
| 6.0 |
0.285" (off chart) |
0.195" |
0.153" |
0.117" |
0.094" |
0.082" |
0.074" |
0.0687" |
| 7.0 |
N/A (off chart) |
0.250" |
0.187" |
0.145" |
0.124" |
0.105" |
0.0905" |
0.082" |
| 8.0 |
N/A (off chart) |
0.307" |
0.232" |
0.180" |
0.1485" |
0.130" |
0.122" |
0.111" |
This chart gives recommendations for width of conductor needed to carry current on different copper thickness.
Stripline Impedance:
Dielectric
Thickness |
|
|
|
Impedance |
|
|
|
|
|
|
|
|
|
|
|
20 |
|
40 |
|
60 |
|
|
|
|
|
|
|
|
|
|
|
Conductor
Width = W |
|
|
|
|
|
|
|
|
|
| 0.002" |
|
0.007" |
|
0.004" |
|
N/A |
|
|
|
|
|
|
|
| 0.003" |
|
0.012" |
|
0.006" |
|
0.003" |
|
|
|
|
|
|
|
| 0.004" |
|
0.016" |
|
0.009" |
|
0.005" |
|
|
|
|
|
|
|
| 0.005" |
|
0.021" |
|
0.0012" |
|
0.007" |
|
|
|
|
|
|
|
| 0.006" |
|
0.026" |
|
0.015" |
|
0.008" |
|
|
|
|
|
|
|
| 0.007" |
|
0.030" |
|
0.018" |
|
0.010" |
|
|
|
|
|
|
|
| 0.008" |
|
0.0035" |
|
0.020" |
|
0.011" |
|
|
|
|
|
|
|
| 0.009" |
|
0.039" |
|
0.023" |
|
0.013" |
|
|
|
|
|
|
|
| 0.010" |
|
0.044" |
|
0.026" |
|
0.015" |
Based on 1 oz. (0.0014") copper conductors separated by polyimide, with a dielectric constant of 3.4 at 1 Mhz. These are for estimation only.
