Product Overview
Specialized diluents, inhibitors and leveling additives let the polysilazane film-former apply smoothly and cure covalently to the substrate at room temperature. The result is ceramic-class surface protection in a clear film: wear resistance, high-voltage electrical insulation, fire-resistant layers and outdoor self-cleaning duty, with short-term substrate-dependent capability to 800 °C.
In hybrid formulations RT7 reaches performance comparable to SILZ-HT21 systems — acids, alkalis, UV and environmental cracking — and has been applied across aerospace, petrochemical, metallurgy, power-generation and defense-related facilities. When a project needs the hardest ambient-cure clearcoat in the line, this is the grade.
Key Benefits
≥8H at room temperature
The hardest ambient-cured film in our range — scratch and wear protection normally reserved for oven-cured ceramics.
500 °C non-yellowing
Long-term color stability at 500 °C and short-term capability to 800 °C (substrate-dependent) keep clear finishes clear.
Insulation-grade clear film
Serves high-voltage insulation and electronic encapsulation duty while staying optically transparent.
30-day chemical endurance
5% NaCl, H₂SO₄ and HNO₃ immersion for 30 days without corrosion; 30-day salt spray clean.
Self-cleaning surface
>110° contact angle plus anti-aging chemistry for exterior architectural and equipment finishes.
Typical Applications
- Clear protective topcoats
- High-voltage electrical insulation
- Wear/fire-resistant layers
- Electronic encapsulation
- Hydrophobic anti-aging exteriors
Solution guides: Electrical Insulation & Electronics ProtectionTransparent, Hard & Easy-Clean Surface Protection
Technical Data
| Test Item | Performance Indicator | Test Method |
|---|---|---|
| Appearance | Light yellow to colorless transparent liquid | — |
| Density | 0.86 ± 0.02 g/mL | — |
| Solid Content (120 ± 2°C) | >55% | — |
| Pencil Hardness | ≥8H | — |
| Adhesion | Grade 0 | — |
| Neutral Salt Spray Resistance | 30 d: no blistering, cracking or rust | — |
| Artificial Aging Resistance | 30 d: no chalking or cracking, slight color change | — |
| Chemical Resistance | 5% NaCl / H₂SO₄ / HNO₃, 30 d: no corrosion | — |
| Water Contact Angle | >110° | — |
| Dry Film Thickness | 20–200 µm (single coat, ≤200 µm) |
| Cure @25 °C (RH 70%) | Surface dry 2 h · full cure >5 d |
| Heat Cure Option | 180 °C: surface dry 6 min, full cure 0.5 h |
| Working Time (after opening) | 6 h |
| Service Temperature | Non-yellowing to 500 °C long-term; short-term to 800 °C (substrate-dependent) |
| Storage / Shelf Life | 5–30 °C · 6 months |
Values from the SILZ-RT7 technical data sheet. Complete TDS with test conditions available on request.
Curing & Processing Guidance
Surface preparation follows the series standard: Sa 2.5 target (minimum St 3), degrease, dry. Shake well and filter through a 400-mesh sieve.
Spray with a 0.5–1.0 mm nozzle in a single coat up to 200 µm dry film. Opened material must be used within 6 hours.
Ambient cure: surface dry in about 1 hour, touch dry past 3 hours, full properties over 3–6 days depending on temperature; 180 °C shortens full cure to 30 minutes. Do not recoat over the cured hydrophobic surface.
Substrate Compatibility
Metals (steel, stainless, aluminum, alloys), glass and ceramic surfaces after standard preparation. For electronics encapsulation and insulation work, validate on your part geometry — our lab supports withstand-voltage test planning.
SILZ-RT7 — Purchasing & Application FAQ
Is SILZ-RT7 really comparable to a baked ceramic coating?
In hardness (≥8H) and surface behavior, yes — that is its design point. Continuous temperature rating (500 °C non-yellowing) sits below the true HT ceramic line, so for 800 °C continuous duty step up to SILZ-HT grades; for everything cured on site, RT7 is the ceiling.
Can RT7 serve as an insulating conformal-style coating?
It is used for high-voltage insulation and electronic encapsulation where a hard, clear, ambient-cured film fits the part. For dedicated conformal coating on electronics with flexibility requirements, compare with SILZ-VR51 and tell us your withstand-voltage target.
Why is my full cure taking several days?
Ambient cure is moisture-driven: at 25 °C / 70% RH plan on >5 days for full properties, faster when warmer or more humid, slower in cold dry air. Surface and touch dry come within hours, so parts are handleable early; use the 180 °C / 30 min schedule when the calendar matters.
How does RT7 differ from RT8?
RT7 maximizes hardness (≥8H) and heat-proof clarity; RT8 adds fluoro-modification for a ≥120° contact angle and anti-graffiti, easy-clean behavior at ≥6H. Pick by which surface property leads your spec.
TDS / SDS / COA & Samples
Technical Data Sheet, Safety Data Sheet and batch Certificate of Analysis are available for SILZ-RT7, and a COA accompanies every shipment. Evaluation samples ship with starting-parameter guidance.
Packaging: Available in 1 kg, 2 kg, 5 kg and 25 kg pails. Shelf life 6 months at 5–30 °C in the original sealed container.
SDS & batch COA on request · Reply within 1 business day.