In modern industrial and consumer electronics, outdoor LED lighting, telecommunications equipment, and automotive components, gaskets are the front line of defense against environmental damage. They must provide an impermeable seal against moisture, dust, and vibration.
However, a standard gasket material will rapidly fail when exposed to prolonged sunlight. Ultraviolet (UV) radiationand the corresponding ozone exposure attack the carbon bonds in organic polymers, leading to cracking, stiffening, loss of elasticity, and ultimately, catastrophic sealing failure.
For industrial users, the solution lies in specialized UV-Resistant Gaskets—specifically, those leveraging advanced silicone and Form-in-Place (FIP) technology. This guide details the science of UV resistance in gasketing and how Incurehelps you implement a long-term, high-performance sealing solution.
The Science of UV Degradation and Resistance
Many common, cost-effective organic rubber materials like natural rubber and Nitrile (NBR) are inherently poor at resisting UV and ozone. This degradation is often accelerated by the high temperatures found in outdoor electronics enclosures.
Why Materials Fail Outdoors
UV radiation supplies the energy needed to break the polymer chains in the gasket material, a process called photodegradation.
- Ozone Attack: UV radiation in the atmosphere creates ozone (O3). Ozone attacks the double bonds in many organic rubbers, causing microscopic cracks on the surface (ozone cracking), which worsen under strain and compression.
- Physical Effects: The material hardens, shrinks, and loses its crucial compression set property—the ability to spring back after being compressed. This leads to gaps, water ingress, and equipment failure.
The Best Defense: Inorganic and Specialized Polymers
Materials that perform best in UV-exposed environments, often recommended for critical, long-term outdoor applications, are those with robust polymer backbones:
- Silicone Rubber: Recognized as a top performer. Because its structure is based on an inorganic silicon-oxygen chain (polysiloxanes) rather than a carbon backbone, it is inherently resistant to UV light, ozone, and oxidation. It also offers excellent thermal stability across a wide temperature range.
- EPDM (Ethylene Propylene Diene Monomer): A synthetic rubber with very good resistance to UV, ozone, and weathering, often serving as a cost-effective alternative to silicone for many outdoor static sealing applications.
- Fluoroelastomers (e.g., Viton™): High-performance materials offering excellent resistance to UV, ozone, and a broad range of chemicals, often used in aerospace and critical automotive applications.
The Next Generation: UV-Curable Form-in-Place Gaskets (FIPG)
While pre-cut silicone and EPDM gaskets are effective, the most efficient and high-performance sealing method today is the UV-Curable Form-in-Place Gasket (FIPG), also known as Cure-in-Place (CIPG).
FIPG technology uses a liquid gasketing material dispensed directly onto the component, cured in seconds, and designed to provide all the resilience of traditional materials with added manufacturing advantages.
FIPG Advantages for UV Resistance
- Instant Cure and Throughput: UV-Curable FIPG materials cure instantly (typically under 15 seconds) when exposed to UV/LED light. This eliminates the lengthy cure times required by Room Temperature Vulcanizing (RTV) silicones (which take hours) and drastically boosts production speed.
- Perfect Fit, Zero Waste: The liquid gasket conforms perfectly to complex geometries, channels, and intricate patterns, resulting in a more reliable seal than pre-cut gaskets, which can be prone to misplacement, stretching, or alignment issues. FIPG also eliminates material waste associated with die-cutting.
- Excellent Compression Set: High-performance UV-Curable FIPG materials, such as specialized Urethane Acrylates and Silicones, are formulated for low compression set. This means they retain their ability to rebound and maintain sealing force even after prolonged compression, ensuring long-term UV-resistant sealing integrity.
How Incure Recommends the Optimal UV-Resistant Gasket
Selecting the right FIPG material requires a deep understanding of the final product’s environment, required compression, and dispensing automation. Incure’s Uni-Seal™ series offers a range of UV-Curable FIP/CIP Gasket solutions designed specifically for durability and rapid manufacturing.
Incure’s 4-Step Gasket Selection Process
- Environment & Chemistry Match:
- External/High UV: We prioritize Silicone-based or specific Urethane Acrylate formulas in our Uni-Seal™ line engineered for exceptional UV and ozone stability, ensuring the gasket won’t degrade over years of outdoor use.
- Chemical/Oil Exposure: If the gasket must resist fuels or aggressive chemicals in addition to UV, we guide you toward Fluorosilicone or chemically resistant acrylated options.
- Mechanical & Re-sealability:
- The required Shore Hardness and Elongation are key. For easily re-sealable enclosures (like battery doors or access panels), products like the Incure Uni-Seal™ 6322 are recommended. This highly resilient material offers excellent “memory retention” (low compression set) and high flexibility (e.g., 560% elongation) to ensure the seal bounces back even after multiple closures. [Table of Incure Uni-Seal™ products with key properties like Shore Hardness and Elongation]
- Dispensing & Viscosity:
- The viscosity must match your automated dispensing equipment and the channel size. We offer products ranging from low-viscosity, self-leveling liquids (ideal for wicking) to high-viscosity, thixotropic gels (Uni-Seal™ 3393VT or 3393GB) that maintain their bead height on vertical or complex surfaces (non-slump).
- Process Integration & Curing:
- We ensure the selected Uni-Seal™ product is compatible with your existing UV/LED curing equipment, guaranteeing a full, rapid cure. Our solutions are 100% solids, eliminating solvents and outgassing, which is crucial for sensitive electronics enclosures.
By partnering with Incure, you move past the limitations of pre-cut materials and implement a modern, automated gasketing process that guarantees superior environmental protection and extended product lifespan.
Ready to Upgrade to a High-Performance UV-Resistant Seal?
The longevity of your outdoor equipment depends on the durability of its seal. UV-Curable FIPG technology offers the robust performance of advanced elastomers with the speed and precision required for modern manufacturing.
Ready to find an Incure Uni-Seal™ FIPG solution that delivers instant, UV-resistant sealing and optimizes your production line?
Would you like to speak with an Incure application engineer about setting up a trial using our UV-Curable gasket material on your enclosure design?