What is a Hydrophobic Coating?
Hydrophobic coatings and treatments are typically utilized to decrease surface energy, repel liquids and other fouling materials or for applications where having a surface that does not wet out when exposed to moisture is desirable.
“Hydrophobic” literally means water repelling, as such a hydrophobic coating results in water molecules being repelled from a treated surface. Hydrophobic coatings and treatments are typically utilized to decrease surface energy, repel liquids and other fouling materials or for applications where having a surface that does not wet out when exposed to moisture is desirable. Most (but not all) hydrophobic coatings are also oleophobic and will also repel oils, solvents, and other organic materials when exposed to them. These repellent coatings have significantly reduced surface energy resulting in a wide variety of uses in many applications.
What Applications Benefit from a Hydrophobic Coating?
There are numerous applications in a wide variety of industries which can benefit from hydrophobic coatings. Examples include optical applications, medical applications,industrial, & consumer applications. Medical devices treated to be hydrophobic benefit from having a surface which repels blood and other liquids. Optical components such as synthetic sapphire used in aggressive industrial applications benefit from having a surface that repels fouling liquids. Numerous consumer applications benefit from having a surface which is more repellent to liquids and oils. In addition a hydrophobic surface can be utilized for improved fingerprint aesthetic behavior. You may benefit from a hydrophobic coating if any of the following apply to your application:
- Functional issue due to liquid behavior on surface
- Surface contamination (fingerprints) degrades a products aesthetic behavior
- Water droplets/contamination impede optical performance
- Surface energy is too high
- Wettability of surface is not ideal
How Are Hydrophobic Coatings Applied?
There are a wide range of options for application of hydrophobic coatings. Examples include:
Selective Deposition Hydrophobic Coating
For applications requiring hydrophobic functionalization of only certain areas manual or automated selective spray/deposition can be utilized. A wide variety of application and nozzle options can support nearly any application and hydrophobic fluid regardless of viscosity.
Dip Applied Hydrophobic Coating
Dip coating can be utilized to treat large batches of parts which require complete treatment of all surfaces. In some cases masking may be needed to prevent treatment of certain areas. Dip coating can be done manually or via automated process which controls insertion and extraction rates. Upside to dip coating is it is a simple process and allows for large volumes of quickly treated parts. Downside to dip coating is the need to properly maintain the bath concentration, mitigate evaporation & dragout losses, in addition to replacement of contaminated bath materials.
Vacuum Deposited Hydrophobic Coatings
Certain hydrophobic treatments are applied via vacuum deposition processes. These are good options for small batches of parts requiring complete treatment. Parts requiring selective treatment can be masked prior to application. Upside to the vacuum deposition process for hydrophobic coatings is repeatability, uniformity of coating thickness, and tight control over coating thickness. Downside to vacuum deposition options is extreme high cost of capital equipment and low throughput due to small batch sizes.
Spray Applied Hydrophobic Coatings
Spray application is an effective and easy to implement coating process for application of hydrophobic coatings to large surfaces or for high volumes of parts. Spray application is flexible as well as parts can be done in line or in a batch process. In addition spray processes can be done manually or automated. Downsides to application by spray are high usage rates due to overspray and also the necessity for masking in some scenarios.
How Do You Solve Your Hydrophobic Surface Issue?
The first step to solving your hydrophobic surface related issue is to reach out to a proven supplier of hydrophobic coatings. Aculon is a leading B2B manufacturer of easy to apply liquid phase hydrophobic coatings. Rather than providing generic off the shelf solutions, Aculon only works on new programs on a case by case basis optimizing a solution for your application that is truly a perfect fit. Together we can help you make winning hydrophobic products.