SiO₂ (silicon dioxide)
Quick answer: SiO₂, also called silicon dioxide or silica, is the ceramic backbone used in many automotive coatings - when it cures it forms a thin, glass-like network that bonds to the clear coat and improves gloss, chemical resistance and water behaviour.
What it means
Most “ceramic” coatings use silica-based chemistry that reacts and cross-links into a Si-O-Si network on the paint. The cured film is transparent, hard and chemically inert. Hydrophobic behaviour (beading or sheeting) comes from the overall formulation and any top-coats rather than SiO₂ alone.
Why it matters
- Durability beyond waxes and simple polymer sealants.
- Improved chemical and UV resistance, helping preserve gloss.
- Enables higher contact angles when combined with hydrophobic groups, giving beading or tuned sheeting.
- Stable base that can be topped up with maintenance products.
Where you’ll see it
Product pages, technical data sheets and marketing claims such as “contains X% SiO₂” for ceramic coatings and glass or quartz-derived products.
Context
Car Paint Protection; Ceramic coatings
Common mistakes
- Confusing silica (SiO₂) with silicone (siloxane oils and polymers) - they are not the same.
- Assuming a higher “% SiO₂” automatically means better performance - prep, solvents, binders and application conditions matter.
- Believing SiO₂ makes paint scratch-proof - it can improve resistance but will not prevent all marring.
- Thinking “ceramic” means a thick layer of glass - coatings are ultra-thin films measured in microns.
Written by Danny Argent. Last updated 06/11/2025 14:55