BISCO® HT-6210 Extra Soft
BISCO® HT-6210 is an extra soft solid silicone rated at 61 Shore OO, designed for the most demanding gasketing applications where extremely low closure force and maximum conformability are required. It delivers 480 psi tensile strength, >20 ppi tear resistance, and a compression set of <25% (22 hours @ 302°F @ 50% deflection). The material is rated for service from -67°F to 392°F and exhibits resistance to UV, ozone, extreme temperatures, and most fluids.
Key Properties
- Durometer, Shore OO: 61 — ASTM D2240
- Tensile Strength: 480 psi — ASTM D412
- Elongation: 565% — ASTM D412
- Compression Set, 22 Hours @ 302°F @ 50%: <25% — ASTM D395
- Specific Gravity: 1.07 g/cc — —
Temperature Range: -67°F to 392°F
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- Specifications
- Applications
- General Info
- FAQs
Physical Properties
| Property | Value | Test Method |
| Material / Substrate | Solid Silicone | — |
| Color | Gray | — |
| Specific Gravity | 1.07 g/cc | — |
| Thickness | 0.010″, 0.020″, 0.031″, 0.063″, 0.125″ | — |
Mechanical Properties
| Property | Value | Test Method |
| Durometer, Shore OO | 61 | ASTM D2240 |
| Tensile Strength | 480 psi | ASTM D412 |
| Elongation | 565% | ASTM D412 |
| Tear Resistance | >20 ppi | ASTM D624 |
| Compression Set, 22 Hours @ 302°F @ 50% | <25% | ASTM D395 |
Thermal Properties
| Property | Value | Test Method |
| Temperature Range | -67°F to 392°F | — |
| Thermal Conductivity | 0.19 W/m·K | ASTM D518 |
Electrical Properties
| Property | Value | Test Method |
| Dielectric Strength | 372 Volts/mil | ASTM D149 |
| Dielectric Constant | 2.76 kHz | ASTM D150 |
| Dissipation Factor | 0.003 kHz | ASTM D495 |
| Dry Arc Resistance | 122 seconds | ASTM D495 |
| Volume Resistivity | 10^14 Ohm-cm | ASTM D257 |
Environmental Performance
| Property | Value | Test Method |
| Low Temperature Brittleness | Pass | ASTM D2137 |
| UV Resistant | Yes | — |
| Ozone Resistant | Yes | — |
- LCD panel gaskets in consumer electronics requiring minimal closure force
- Digital camera lens and battery hatch seals requiring precise conformability
- Underwater lighting gaskets demanding watertight sealing at very low sealing loads
- Industrial, medical, and electronic gasketing where high-performance compliance is required
- Battery compartment seals in portable and handheld devices
Common industries: Consumer electronics, industrial equipment, medical devices, telecommunications.
BISCO® HT-6210 is an extra soft solid silicone measured on the Shore OO scale at 61, indicating a level of compliance far beyond what Shore A grades can express.
It is specifically engineered for gasketing applications where the sealing force available is extremely low — such as LCD gaskets, digital camera lens gaskets, battery hatch seals, and underwater lighting assemblies — and where the gasket must conform precisely to irregular surfaces to achieve a reliable seal. Extremely tight thickness tolerances support gasket integrity in precision consumer electronics and industrial applications.
The material provides 565% elongation and passes low temperature brittleness testing per ASTM D2137. Its electrical insulation properties include 372 Volts/mil dielectric strength, 10^14 Ohm-cm volume resistivity, and 122 seconds dry arc resistance, making it suitable for electronic enclosure sealing applications. It resists UV degradation and ozone.
What differentiates BISCO® HT-6210 from Shore A-rated solid silicones?
BISCO® HT-6210 is rated on the Shore OO scale at 61, which corresponds to a level of softness far beyond the lower end of the Shore A scale. This extra soft profile enables a highly protective seal with minimal closure force, making it the appropriate selection for delicate electronic assemblies — such as LCD panels and camera lens gaskets — where conventional Shore A grades would require too much sealing force and risk damaging the mating components.
Why is compression set an important consideration for solid silicone elastomers?
Compression set measures how well an elastomer recovers its original thickness after sustained compression. In sealing applications, a material with high compression set will permanently deform over time, reducing sealing force and allowing leak paths to develop. BISCO® HT-6210 achieves <25% compression set (22 hours @ 302°F @ 50% deflection per ASTM D395), supporting long-term sealing integrity even under elevated temperature conditions.
What is the temperature range for BISCO® HT-6210?
BISCO® HT-6210 is rated for service from -67°F to 392°F, as listed on the TDS.
Is BISCO® HT-6210 suitable for electronic sealing applications?
Yes. The TDS lists dielectric strength of 372 Volts/mil, volume resistivity of 10^14 Ohm-cm, dry arc resistance of 122 seconds, and UV and ozone resistance, supporting its use in electronic enclosure and device sealing applications. No specific compliance standards are cited on the TDS.
How should BISCO® HT-6210 be specified?
Specify grade (BISCO® HT-6210), thickness, dimensional tolerances, and finished format.
