The term “fogging” refers to the condensation of water vapor on a plastic film surface. This phenomenon occurs when the air temperature around the polymer film is lowered to dew point, resulting in a temperature difference between the inner and outer layers of the polymer film. The extent of this phenomenon depends on the relative humidity of the surrounding air and the temperature of the polymer film.
Antifog masterbatches prevent the formation of this fog inside of a plastic film used in agricultural and food packaging applications.
In food packaging films the droplets makes the content less visible and may deteriorate the quality of the packed food product. In agricultural applications as greenhouses, fogging will affect the transmittance of light, causes burns of the crops by the lens effect of the droplets, and a continuous water drip. Typical Polyolefins are very hydrophobic. Water on a film surface will cause the formation of droplets (high contact angle: no wetting or spreading of the water over the surface). Antifog masterbatches increase the surface energy of the film to the point where it is balanced by the surface energy of the water droplets. This prevents the fogging phenomenon and increases the transparency of the plastic film.
Ciba Polymer Kabir has developed an innovative range of antifog masterbatches that help reduce the harmful effects of water drops on packaging and agriculture films.