Die-cut gaskets add inventory, alignment steps, and scrap. A light-curable liquid gasket removes all three: a robot lays a bead exactly where the seal belongs, a lamp cures it in seconds, and the part moves on. For enclosures produced in volume, it changes the economics of sealing.

FIP Versus CIP: Two Related Processes

Both start from the same dispensed liquid, but the sequence differs.

• Cure-in-place gasket (CIPG): the bead is dispensed onto one flange, cured to a solid compressible profile, and the mating part is assembled later. The gasket behaves like a bonded-on rubber seal and can be opened and reclosed.
• Form-in-place gasket (FIPG): the bead is dispensed and the parts are mated while it is still liquid, so it cures in the compressed gap and fills every contour. This gives the tightest seal but is not designed for disassembly.

Light-curable chemistries, usually acrylated urethanes or UV-cure silicones, suit CIPG especially well because the cure is fast and does not depend on trapping the resin between two surfaces.

Why Manufacturers Switch to Light-Cure Liquid Gaskets

• Cycle time: cure in 2 to 30 seconds under a UV lamp versus minutes to hours for a moisture-cure sealant.
• No pre-cut inventory: one cartridge covers many housing geometries; design changes do not scrap gasket stock.
• Conformal sealing: the liquid fills machining marks, radii, and complex paths a flat gasket bridges over.
• Automation fit: consistent bead from a servo dispense valve, repeatable placement, and inline cure integrate with existing conveyors.
• Low compression set: cured elastomeric grades recover after clamping, holding sealing force over the service life.

Email Us with your flange geometry, seal path length, and environmental requirements, and our team will help select a grade.

Real Incure Grades

The Incure Uni-Seal line covers light-curable sealing and gasketing:

• Uni-Seal 6322 and 6322R: low-viscosity, high-elongation gasket grades that form an air-tight, high-memory seal and are offered in several colors for line identification.
• Uni-Seal 3393: a peelable, tough, low-CTE electronics sealant well suited to enclosures that may need rework.
• Uni-Seal 3718F: a fast-cure flexible encapsulant and sealant with a secondary heat cure for shadowed areas.
• Uni-Seal 6213HT: a low-shrinkage, chemically resistant potting and sealing grade for electronics.

Thicker T, VT, and gel variants are available where the bead must hold height on a vertical flange.

Design and Process Considerations

Confirm the bead cross-section gives the compression the joint needs, typically 15 to 40 percent, at the assembled gap. Provide a light path to the full bead; deep grooves may need an angled lamp or a grade with a secondary moisture or heat cure for the shadowed base. Check substrate adhesion for CIPG, where the gasket must stay attached to one flange during handling. For sealed electronics, differential expansion between a metal housing and a plastic cover stresses the seal, so review how CTE mismatch causes bond and seal failure.

Testing a Liquid Gasket

Qualify a light-curable gasket the same way you would a molded seal. Compression set measures how much sealing force is lost after the gasket is held compressed at temperature for a set period; lower is better, and it predicts whether the seal holds over years of clamped service. Ingress protection testing to an IP rating verifies the assembled housing keeps out dust and water. Compression-deflection data shows how much force the bead generates at the design gap, which the fastener pattern has to overcome without crushing the bead flat. Aging exposes samples to heat, humidity, ozone, and any service chemicals, then repeats the seal test.

Run these on the actual bead geometry and cure recipe, not a slab sample, because bead cross-section and cure completeness both change the result. Record the cure dose used, since an under-cured gasket shows higher compression set and lower chemical resistance than the datasheet value. Keep witness samples from production lots for retest if a field seal is questioned. It is also worth checking adhesion of the cured bead to the flange after aging, since a gasket that stays put during assembly can still lift at a corner after months of thermal cycling, opening a leak path even though the elastomer itself is intact.

Where They Are Used

Light-curable FIP and CIP gaskets seal electronic enclosures and connectors, automotive lighting and control modules, solar inverter and telecom outdoor cabinets, appliance housings, and instrument cases. Cure is handled with a UV LED flood lamp at a station or an inline UV conveyor system for continuous production.

Closing

Light-curable liquid gaskets trade gasket inventory and alignment labor for a dispense-and-cure step that seals complex flanges consistently. Success depends on bead geometry, a clear light path, and verified adhesion. Contact Our Team to review your sealing application.

Visit www.incurelab.com for more information.