A thin dielectric sealer that’s perfect for coating a flat electronic assembly runs straight off a vertical furnace wall before it has a chance to cure, and a thick, non-sagging paste made for filling a large void is needlessly heavy-handed on a simple flat seal. Incure’s Epo-Weld™ high temperature silicone sealer line solves that mismatch with three grades that share identical mechanical and electrical properties and differ almost entirely by viscosity — a genuine viscosity ladder rather than three products competing on strength or temperature rating. All three are also single-part, room-temperature-cure formulations, so there’s no mixing ratio or pot life to manage on the shop floor regardless of which viscosity a job actually calls for — the only real decision is where the joint sits on that ladder.
A Three-Step Viscosity Ladder From Thin Coating to Non-Sag Paste
HTSS-260 sits at the thin end at 200–300 cP, a clear, flowable sealer built for coating ceramics, metals, and glass in electronic assemblies where a thin, even hydrophobic film matters more than gap-filling capacity. HTSS-261 steps up to 2,000–4,000 cP specifically to solve the problem HTSS-260 can’t — sealing porous ceramics and refractories on vertical surfaces, where a low-viscosity sealer would run off before curing. HTSS-263 goes further still to 18,000–25,000 cP, a very high-viscosity paste engineered to stay exactly where it’s placed during application and cure, built for filling large voids and gaps in ceramic insulators rather than coating a surface at all. Moving up that ladder trades flowability for gap-filling and vertical stability, and picking the wrong end of it means either watching a thin sealer run off a vertical joint or applying a thick paste where a simple flat coating would have worked just as well with less material and easier application. The roughly two orders of magnitude separating HTSS-260’s thinnest rating from HTSS-263’s thickest is a wider spread than viscosity variants typically show on Incure’s other product lines, reflecting how differently a coating film, a vertical seal, and a void-filling paste actually behave during application even before cure begins.
Mechanical and Electrical Properties Stay Identical Across All Three
All three grades share the same Shore D80 hardness, 9,600 PSI flexural strength, 1,600 PSI tensile shear, 800°F temperature ceiling, and 24-hour room-temperature cure — none of that changes as viscosity climbs from HTSS-260 to HTSS-263. Each also delivers the same dielectric strength and flexibility, preventing electrical leakage and prohibiting the coating from fracturing under thermal stress, and the same resistance to humidity, chemical vapors, and UV exposure. That consistency is what makes viscosity the entire selection variable here — a facility isn’t trading away strength, temperature rating, or electrical protection by choosing the thinner grade for a flat seal instead of defaulting to the thicker paste out of caution.
Email Us with your joint orientation — flat, vertical, or a void that needs filling — and Incure’s engineers can confirm which Epo-Weld™ silicone sealer viscosity actually fits.
Matching Each Grade to the Joint It Was Actually Built For
HTSS-260’s thin, flowable consistency makes it the natural choice for sealing electronic assemblies where the coating needs to stay thin and even across ceramic, metal, and glass surfaces without adding bulk. HTSS-261’s mid-range viscosity is specifically formulated to hold its position on a vertical surface, the difference between a sealer that actually seals a heater end or instrument housing mounted upright and one that slides down and pools at the bottom before cure locks it in place. HTSS-263’s non-sagging paste consistency is built for a genuinely different job — not coating a surface but filling a real void, whether that’s a gap in a ceramic insulator or the space around a terminated heater lead — where the sealer has to hold its own shape and bridge a real distance rather than flow into a thin film. Confirming the actual gap size or surface orientation before ordering is worth doing directly rather than estimating, since the wrong viscosity choice on this particular line shows up immediately during application rather than only surfacing later in service.
Where the Line Fits
Electronic assembly sealing and moisture protection on ceramic, metal, and glass components favors HTSS-260’s thin, even coating. Vertical furnace, refractory, and instrument housing sealing relies on HTSS-261’s mid-viscosity stability specifically to avoid the running and sagging a thinner sealer would suffer in that orientation. Large-void filling and heater lead termination in ceramic insulators depend on HTSS-263’s thick, non-sag paste to bridge real gaps rather than coat a surface. Facilities already running Incure’s high temperature glass coatings line or high temperature inorganic binder line for refractory sealing and formulation work can add this silicone sealer line specifically where the requirement is a flexible, dielectric seal rather than a rigid ceramic coating or a formulation ingredient.
Contact Our Team to confirm the Epo-Weld™ silicone sealer grade for your joint geometry.
Visit www.incurelab.com for more information.