24 non-woven fabrics made of polyester, rayon/polyester and/or polyester/polychlal for the manufacture of air filters to be used in building, office and factory air conditioners, in factory painting booths, in air compressors, engines and blowers, in ventilators for magnetic devices in electronic equipment, in air circuits of automatic controllers, in heating apparatus and air cleaners; and in the manufacture of interfacing for clothing