UV Silicone Adhesives & Sealants — Pyra-Sil™

High-temperature silicone adhesives that cure in seconds under UV light — with secondary moisture cure ensuring full bond strength in shadow and hidden areas. Rated −45°C to 260°C for FIPG, conformal coatings, PCB protection, and industrial sealing.

Silicon wafer die grid showing semiconductor circuit patterns for Pyra-Sil™ UV silicone conformal coating on PCBA
Conformal Coatings on PCBA
Protects populated circuit boards against moisture, humidity, condensation, and thermal stress — with UV inspection fluorescence confirming full coverage.
Industrial conduit and pipe bundle along concrete wall for Pyra-Sil™ UV silicone form-in-place gasket FIPG sealing
Form-In-Place Gaskets (FIPG)
Creates on-demand seals directly on mating surfaces of electronics housings, automotive enclosures, and industrial assemblies — replacing cut gaskets.
Electronic component assembly under purple-teal UV light for Pyra-Sil™ UV silicone electronics potting and encapsulation
Electronics Potting & Encapsulation
Flexible encapsulation protects sensitive components from shock, vibration, moisture, and thermal cycling without cracking or delaminating.
Industrial factory interior with moody teal light for Pyra-Sil™ UV silicone shadow and hidden joint sealing
Shadow & Hidden Joint Sealing
Dual-cure chemistry reaches areas UV light cannot access — moisture curing ensures full cure depth in joints, overlaps, and enclosed bond lines.
Large yellow industrial pipes on building exterior for Pyra-Sil™ UV silicone automotive and industrial sealing
Automotive & Industrial Sealing
Weatherproof, ozone-resistant bonds on metals, plastics, and glass — surviving continuous service from −45°C to 260°C in harsh under-hood and process environments.
Telecommunications antenna on snow-covered mountain peak for Pyra-Sil™ UV silicone high-altitude outdoor protection
High-Altitude & Outdoor Protection
Guards PCBs and sensitive assemblies against moisture, condensation, and electrical arcing in high-altitude environments and outdoor industrial installations.
  • UV/moisture dual-cure silicone uses two independent cure mechanisms. UV light triggers rapid cure in exposed areas — achieving fixation within seconds to minutes. Areas in shadow (under components, inside joints, or behind opaque substrates) cure via atmospheric moisture over 24–72 hours. This ensures complete cure across the entire application regardless of UV accessibility.

  • Most Pyra-Sil™ UV silicone grades achieve UV fixation in 120 seconds under standard UV light in the 365–405 nm range. Grade 865 cures in approximately 300 seconds. Shadow areas complete cure via moisture within 24–72 hours depending on humidity and film thickness.

  • All Pyra-Sil™ UV silicone grades are rated from −45°C to 260°C — covering automotive, industrial, and outdoor electronics applications exposed to extremes of temperature.

  • Pyra-Sil™ UV silicone is used for conformal coating on PCBA, form-in-place gaskets (FIPG), electronics potting and encapsulation, shadow-area sealing in connector backshells, automotive and industrial sealing, and high-altitude or outdoor electronic protection.

  • Yes. The moisture-cure secondary mechanism ensures full cure in shadow areas that UV light cannot reach — under tall components, inside cavities, and behind opaque parts. This eliminates uncured adhesive in complex assemblies where pure UV-cure adhesives would leave uncured pockets.

  • Yes. Cured Pyra-Sil™ UV silicone resists ozone, UV degradation, harsh weather, high humidity, and thermal cycling from −45°C to 260°C. It is widely used as a conformal coating on outdoor electronics, communications equipment, and high-altitude PCBs.

Ready to Specify Pyra-Sil™ UV Silicone Adhesives & Sealants?

Tell us your substrate, operating temperature, and UV accessibility —
our team will recommend the right UV silicone grade and pack size for your assembly.