Die-cut gaskets waste up to 60% of the rubber sheet they’re stamped from, take up inventory space in dozens of part numbers, and still leave a mechanical seam a liquid-dispensed alternative simply doesn’t have — which is why UV Cure-In-Place Gasket technology has moved from a niche process to a mainstream sealing method in under a decade.
What UV CIPG Actually Is
UV CIPG stands for Ultraviolet Cure-In-Place Gasket: a liquid elastomer dispensed onto a component’s flange with automated equipment and immediately cured into a solid, resilient gasket using high-intensity UV light — before the parts are ever assembled together. That sequencing distinguishes it from a Form-In-Place Gasket, where the material is still wet when the parts are joined and cures afterward inside the closed joint.
The Cure Mechanism
Photoinitiators within the resin absorb energy from UV light, typically in the 365nm to 405nm range, and release free radicals or cations that drive rapid polymerization. The reaction completes in five to thirty seconds, compared to the roughly 24 hours a room-temperature-vulcanizing silicone needs, letting a part move to inspection and final assembly almost immediately rather than sitting in a drying rack.
CIPG vs. FIPG: Why the Distinction Matters
CIPG produces a dry, non-tacky elastomer that seals through mechanical compression once the parts are mated — useful when a housing might need to be opened later for servicing without destroying the gasket. FIPG instead cures inside the joint itself, forming a permanent bond and seal that makes disassembly difficult without damage. UV CIPG effectively delivers the automation benefits of a dispensed liquid material with the serviceability of a traditional die-cut gasket.
Where the Real Savings Come From
Automated dispensing robots can trace complex 3D paths, thin walls, and intricate grooves that a die-cut gasket geometry simply can’t replicate, letting engineers shrink housing designs without sacrificing seal integrity. Material waste drops from the 40–60% typical of die-cutting to essentially zero, since only the exact volume needed is dispensed. Inventory simplifies dramatically too — a manufacturer stocks a handful of resin types instead of hundreds of gasket part numbers, since the gasket’s shape lives in the robot’s programming rather than in a physical die.
Chemistry Options
Urethane acrylates are the most common UV CIPG chemistry, offering a wide hardness range and strong adhesion across substrates with fast cure speed. UV-curable silicones extend that performance to extreme temperature ranges — up to 200°C or down to -50°C — combining silicone’s thermal stability with UV curing’s process speed. Dual-cure formulations address deep or shadowed bead geometry by curing the exposed surface under UV light while a secondary moisture or heat mechanism finishes the material the light couldn’t reach.
Where UV CIPG Is Used
Automotive electronics rely on it to seal ECUs, sensor housings, and EV battery packs, where chemical resistance to automotive fluids and stability across wide temperature swings are non-negotiable. Consumer electronics use it for IP67/IP68-rated water and dust sealing on smartphones and wearables, where beads thinner than 0.5mm are routine on compact plastic or metal housings. Aerospace and defense applications favor the weight reduction UV CIPG offers over mechanical seals, without giving up sealing performance in pressurized environments. For adhesive-and-plastic combinations that see similar sealing and bonding demands, Incure’s Uni-Weld™ Plastic Bonder line covers a comparable range of substrate compatibility.
Getting the Implementation Right
Substrate compatibility testing comes first — some plastics like PP or PE need plasma or corona treatment before a UV CIPG material will adhere reliably during automated dispensing. Dispensing equipment selection is equally critical: high-accuracy volumetric or jetting valves paired with multi-axis robots maintain the consistent bead height and width that prevents both leaks and over-compression. Email Us for guidance on matching dispensing equipment to your specific bead geometry before committing to a resin formulation.
Shore Hardness and Compression Set
Shore Hardness, measured on the A or 00 scale, dictates how much force is needed to compress the gasket — softer grades around Shore A 20-30 suit plastic housings prone to warping under high compression, while harder grades in the Shore A 60-70 range fit rigid metal housings needing a more robust seal. Compression set — the percentage of deflection the material fails to recover after sustained compression — should be as low as possible, since a gasket that doesn’t spring back loses sealing pressure and reliability over the product’s service life. Housings that mix plastic and metal flanges also inherit the same CTE mismatch challenge documented in adhesive bond failures, which a gasket with adequate elongation needs to absorb rather than transfer into a crack at the seal line.
Common Failure Modes
Oxygen inhibition can leave acrylate-based resins slightly tacky at the surface; higher-intensity UV exposure or a resin specifically formulated to resist this effect resolves it. Shadowing in deep, narrow grooves blocks UV light from the sidewalls, addressed through better lamp orientation or a dual-cure material. Adhesion loss traces back almost every time to surface contamination from oils or mold-release residue, which proper cleaning or a primer/plasma pretreatment step eliminates.
Where This Technology Is Headed
Smart dispensers that adjust flow rate in real time based on temperature and viscosity changes are becoming more common, and full traceability — exact resin volume dispensed alongside the precise UV dose applied — is increasingly valuable for compliance and quality audits in aerospace and other high-reliability sectors.
Contact Our Team for guidance on selecting a UV CIPG chemistry and dispensing setup matched to your specific sealing application.
Visit www.incurelab.com for more information.