Understanding Hydrophobics
Understanding Hydrophobicity and Its Role in Automotive Protection
Ceramic coatings are often described as “hydrophobic” or even “self-healing,” but if you’re just beginning to explore automotive protection products, you might wonder why these features matter. In this blog, we’ll break down the concept of hydrophobicity, explain its significance for automotive care, the science behind it, and highlight what to look for when selecting a hydrophobic coating.
What Does Hydrophobic Mean?
Hydrophobicity refers to a material’s ability to repel water.
To understand hydrophobic surfaces, it helps to learn about contact angle — a measure of how water interacts with a surface. You can observe this by measuring the angle between a droplet of water and the surface it rests on. The smaller the angle, the more the water spreads out.
Water spreading out with a low contact angle on a non-coated surface (left) vs water beading up on a ceramic coated surface with a high contact angle (right)
Contact Angle Categories:
0 Degrees: “Perfect wetting,” where water spreads completely across the surface.
90 Degrees or More: Considered hydrophobic, where water beads up rather than spreading.
150 Degrees or More: Known as “super-hydrophobic,” where water barely touches the surface.
Many materials found in nature are hydrophobic. Butterfly wings have a contact angle of around 130 degrees, duck feathers are super-hydrophobic at 150 degrees, and rose petals go even further at 160 degrees. Even human skin falls into the hydrophobic category with a contact angle of 90 degrees. While nature achieves hydrophobicity through diverse methods, ceramic coatings replicate and enhance these properties for automotive protection.
How Do Ceramic Coatings Achieve Hydrophobicity?
Ceramic coatings create hydrophobic surfaces through three primary methods:
Surface Smoothing: Reducing microscopic imperfections that allow water to cling.
Chemical Water Repellency: Using compounds that repel water molecules.
Rare-Earth Dioxide Infusion: Incorporating materials like titanium dioxide to increase hydrophobic performance.
Surface Smoothing:
Even brand-new automotive paint has tiny pits, ridges, and pores that give water places to stick. Ceramic coatings contain nano-sized particles that fill in these imperfections, creating a smoother surface where water has fewer “handholds.” Once applied, these particles harden, making the surface more water-repellent.
While smoothing the surface alone can produce good results, high end coatings use two more methods in conjunction with smoothing to achieve the incredible results coatings are known for.
Chemical Water Repellency:
Hydrophobicity is also a chemical property. Chemicals are usually classified in one of two categories; hydrophobic - does not mix with water, and hydrophilic - mixes readily with water. Some coatings and detail products use chemical additives that are hydrophobic so they will repel water by nature.
Most of these additives can degrade over time, reducing effectiveness fairly quickly. That is why higher end brands use a less common yet more effective method.
Rare-Earth Dioxide Infusion:
Premium ceramic coatings, like Fireball, combine silica-based self-leveling particles with rare-earth oxides such as titanium dioxide. These oxides have unique electron structures that prevent water molecules from adhering, delivering extreme hydrophobicity and long-lasting protection.
At our shop, we install Fireball Ceramic Coatings. Fireball combines the first method, using nano particles to self level and make the surface more level, and the less common third option, rare-earth dioxide infusion. This creates water contact angles that exceed 150 degrees making for a super-hydrophobic surface. But why go through all that trouble? What is the benefit of a hydrophobic surface?
Why Do Car Owners Love Hydrophobic Surfaces?
Hydrophobic coatings offer numerous benefits for vehicle owners, often marketed with terms like “self-cleaning.” While some claims may sound exaggerated, the advantages are real:
Key Benefits:
Anti-Icing & Anti-Corrosion: Reduces damage from water exposure. Repelling water means water spends less time on the surface. That means as the weather cools and freezes, there is less water available to turn to ice. There is also less water available to sit in areas to begin corrosion.
Mineral Build-Up Resistance: Prevents deposits that can accumulate from heavy rain, snow, and hard water. When water or snow with trace minerals is allowed to sit on a surface, the minerals settle and build up on the surface as the water evaporates, becoming difficult and labor intensive to remove.
Graffiti and Chemical Resistance: Shields against contaminants. The more hydrophobic a surface is, the more difficult of a time anything has to stick to it. Sea salt, chemical fallout, and even spray paint will have a more difficult time sticking to the surface. Many harmful substances are carried in liquids that can come to rest on your vehicle for long enough to do long term damage.
Weathering Protection: Slows down fading and degradation. The longer chemicals and the contaminants in water and chemicals are allowed to linger on your paint, the more the compounds in them do to settle into those crevices and etch themselves into the finish. The quicker water and those chemicals can remove themselves from the finish, the less chance those minerals and compounds have to settle and dry onto the surface.
Many hazards, such as mineral buildup or corrosion, stem from prolonged water exposure. Hydrophobic coatings minimize water contact, preventing harmful substances from settling and causing damage.
Self-Cleaning Effect:
Being hydrophobic has some other cool byproducts as well. Since many contaminants are first introduced to the surface of a vehicle via rain, road spray, mud, and the like, preventing the water containing those things from sticking is often touted as “self-cleaning”. On super-hydrophobic surfaces, contaminants bead up like water and rinse away easily during washing. This reduces the chance of scratches and preserves paint quality.
Additional Perks:
The hardened ceramic layer cures to a very high hardness, often much in excess of your vehicle’s original finish. This means the coatings enhance scratch and swirl resistance, adding further protection against wear and tear.
Choosing the Right Ceramic Coating
By now, you likely have a good idea of what you need in a hydrophobic coating. To summarize, Fireball coatings focus on three key elements for superior hydrophobic performance:
Self-Leveling Nano-Particles
Rare-Earth Dioxide Infusions
Contact Angles Above 100 Degrees
All Fireball coatings include titanium dioxide infusions, ensuring outstanding hydrophobic properties. Even the most basic option meets the scientific threshold for hydrophobicity.
Pro Tip:
Ceramic coatings should always be applied by trained professionals to ensure proper performance. Professional grade ceramic coatings are no joke. They contain higher concentrations of “solids” which are the self leveling ceramic particles and rare earth dioxides. Because of a higher concentration of these and a lower concentration of “carrier agents” or solvents in which those solids are suspended for application, the application process is specialized and there are some very important nuances that your installer is trained to monitor for and recognize throughout the process to ensure the coating is bonding properly. Fireball-certified installers undergo rigorous training through Fireball Academy to guarantee quality results.
Final Thoughts: Protecting Your Investment
We’ve covered the science behind hydrophobicity, how ceramic coatings achieve it, and why it benefits car owners. Whether you’re looking to simplify maintenance, prevent damage, or keep your vehicle looking showroom-new, hydrophobic ceramic coatings deliver exceptional results. Hydrophobics aren’t the only consideration though. There are other factors that change between coatings and manufacturers such as longevity, heat resistance, scratch resistance ability, compatability with other car-care products, and the ability to use the coating on different surfaces such as interior, exterior, glass, wheels, etc. It is always best to discuss these things with a certified installer that you trust who can put together a package that suits your needs and meets your goals.
Ready to protect your car? Contact us today or request a free quote online!