Anti-fog

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Anti-fog agents, also known as anti-fogging agents and treatments, prevent the condensation of water on a surface in the form of small droplets which resemble fog. Anti-fog treatments are often used for transparent glass or plastic surfaces in optics, such as the lenses and mirrors found in glasses, goggles, camera objectives, and binoculars. Anti-fog treatments work by minimizing surface tension, resulting in a non-scattering film of water instead of single droplets, an effect called wetting. Anti-fog treatments usually work either by application of a surfactant film or by creating a hydrophilic surface.

1 Application
2 Agents
3 Home recipes
4 See also
5 References
6 External links

[edit] Application

Anti-fog agents are usually available as spray solutions, cremes and gels, and wet tissues. More resistant coatings are often applied in complex manufacturing processes. Anti-fog additives can also be added to plastics where they exude from the inside to the surface ^[1].

[edit] Agents

The following substances are used as anti-fog agents:

Surfactants that minimize the surface tension of the water:
- Detergents, including shampoo and soap, applied as a solution and wiped off without rinsing
Hydrophilic coatings that maximize the surface energy:
- Hydrophilic polymers and hydrogels:
  - Gelatin, applied to glass and plastics as a 2% solution for 30 min, then rinsed
- Hydrophilic colloids and nanoparticles:
  - Titanium dioxide, becomes highly hydrophilic under UV light

[edit] Home recipes

Many home recipes exist to prevent fogging, the easiest being to apply a thin film of detergent. Many of these advices do not work, including vinegar and ammonia.