The automobile air filter is used to protect the engine and prevent damage to the motor components by dust, contaminants and other harmful suspended particles in the air. The latest evolution in the filtration industry is the use of nanotechnology in this field. With this technique, the surface of large cellulosic or synthetic nanofibers (usually 10 to 30 micrometers in diameter) is covered with a layer of ultra-fine nanofibers (typically 50 to 400 nm in diameter). There are two different methods for separating particles in the filter paper structure.

In-depth filtration, in which particles are separated in different layers of paper according to their size; and surface filtration, in which all particles are separated on the surface of paper. In Behran Co. before the pleating process, the filter paper is covered with a layer of Polyamide textiles with the diameter of less than 100 nanometers by using electrospinning process.