DOWSIL 3-4222
Harmonization Code : 3506.91.90.99 | Prepared glues and other prepared adhesives, not elsewhere specified or included; products suitable for use as glues or adhesives, put up for retail sale as glues or adhesives, not exceeding a net weight of 1 kg ; Adhesives based on polymers of headings 3901 to 3913 or on rubber; Other ; Other

Main features
- 30-Minute Cure Cycle
- Visual 1:1 Mix Verification
- 14 kV/mm Dielectric Strength
Product Description
DOWSIL™ 3-4222 Dielectric Firm Gel Kit is a two-part, addition-cure silicone gel for potting printed circuit board system assemblies. The blue Part A and yellow Part B are mixed 1:1 and form a translucent green material, giving operators a visible indication of component loading and mixing. The mixed gel has a typical viscosity of 325 mPa·s, cures in 30 minutes at 25°C, and can be heat accelerated to 2 minutes at 100°C or 1 minute at 125°C. After cure, the firm gel provides electrical insulation, environmental protection, mechanical cushioning, and stress relief while retaining the repairability associated with silicone gels. Conditional primerless adhesion may be obtained at room temperature, but adhesion and cure compatibility should be verified in the intended design and environment.
Key features
- Fast room-temperature or heat-accelerated cure: 30-minute cure at 25°C, with shorter thermal cure options for faster processing.
- Color-coded 1:1 mixing: Blue and yellow components turn green when properly mixed, supporting visual process control.
- Firm dielectric gel protection: Shore 00 hardness of 39 with 14 kV/mm dielectric strength for protected electronic assemblies.
Applications
- Potting and encapsulation of printed circuit board system assemblies
- Electrical insulation and environmental protection of boards, components, and assemblies
- Stress relief and mechanical protection for delicate electronic components and interconnections
Technical Specifications
Physical Properties
General Properties
Electrical Properties
Additional Information
DOWSIL™ 3-4222 Dielectric Firm Gel Kit
A low-viscosity, two-part silicone firm gel for PCB potting and encapsulation. Its 1:1 color-coded mix cures at room temperature or with heat acceleration, forming a translucent green dielectric gel that supports electrical insulation, environmental protection, and stress relief.
DOWSIL™ 3-4222 Dielectric Firm Gel Kit
As-supplied properties
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| Viscosity, Part A | 350 | mPa·s | Typical, as supplied |
| Viscosity, Part B | 325 | mPa·s | Typical, as supplied |
| Viscosity, mixed | 325 | mPa·s | Typical, after 1:1 mixing |
| Specific gravity, Part A | 0.97 | — | Typical, uncured |
| Specific gravity, Part B | 0.98 | — | Typical, uncured |
| Mix ratio | 1:1 | — | Part A to Part B |
| Component colors | Blue / yellow | — | Parts turn translucent green when mixed |
Mixing, dispensing, and cure
Combine Part A and Part B in the specified 1:1 ratio and mix until the material is uniformly green. Matched viscosities permit manual mixing for low-volume work or static and dynamic meter-mix equipment for higher-volume dispensing. Control air incorporation and verify the cure schedule in the actual assembly.
Recommended process sequence
Shelf life is 12 months at 25°C. Follow the use-by date and storage conditions on the product label. Read the product Safety Data Sheet and container label before handling.
Application and compatibility guidance
Cured electrical and physical properties
Typical values are provided for product evaluation and are not intended as specification limits. Confirm performance in the final assembly, geometry, and exposure conditions.
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| Specific gravity, cured | 0.97 | — | Typical |
| Refractive index | 1.4 | — | Typical |
| Durometer | 39 | Shore 00 | Typical cured hardness |
| Dielectric strength | 350 / 14 | V/mil / kV/mm | Typical |
| Dielectric constant | 2.64 | — | At 100 Hz |
| Dielectric constant | 2.64 | — | At 100 kHz |
| Volume resistivity | 1.0 × 10¹⁵ | Ω·cm | Typical |
| Dissipation factor | 0.0007 | — | At 100 Hz |
| Dissipation factor | 0.0002 | — | At 100 kHz |
| Thermal conductivity | 0.15 | W/m·K | Typical value listed on the current Dow product page |
Applications
The firm gel is intended for potting PCB system assemblies where a soft, resilient dielectric material is needed around components and interconnections.
Encapsulants and gels selection guide
Technical support for DOWSIL™ 3-4222 Dielectric Firm Gel Kit
Need help evaluating mix and dispense equipment, cure conditions, cure-inhibition risks, adhesion, or gel performance in your PCB assembly? Krayden can help review your process requirements and identify the product testing needed for your design.





















