(JP2014144420) 1. Electrospinning nanofibers prepared by the application of an antimicrobial and an antimicrobial air filter medium. 2. Imparting an antimicrobial property to the polymer solution at 1-50% PHR as antimicrobial agent, preferably a 4-25% composite solution was added to the layer of electrospun nanofibers on the substrate is laminated on the base material or a different type of coating on the layer of nanofibers, wherein the 2-layer structure of claim 1 Huntersville and filtration of the air filter. 3. Imparting an antimicrobial property to the polymer solution at 1-50% PHR as antimicrobial agent, preferably added 4-25% electrospun nano-fiber composite solution on the substrate layer is laminated on a base material or another type of nanofibers is coated on a layer of, further comprising at least 3 on the one or more of the structures and the cured layer characterized in that the antimicrobial air filter media of claim 1 and. 4. In terms of filter performance required for the air filter and the nanofiber layer to have, a different type of the solution is a solution of the composite of claim 2 electrospun nanofiber layer produced by, on the substrate is layered on top of the substrate or composite of claim 2 solution coated on the nanofiber and wherein the antimicrobial air filter media of claim 1. 5. The composite nanofibers layer due to the expression of the anti-microbial solution not only limitation is given thereto in terms of filter performance, composite solution in a solution of a type different from the target value of the nanofiber layer in terms of filter performance is present in an amount that is insufficient to supplement the claim 1 Huntersville characterized in that the air filter and the filter media. 6. Claim 4 or claim 3 within layers of the multilayer structure, the fiber diameter of at least one 50-500 nm, preferably 100-200 nm and wherein the antimicrobial air filter medium of claim 1. 7. 100 μm or less and the size of the antimicrobial agent, in combination with a nanocomposite nanofibers, the nanofibers and characterized in that the air filter medium claim 1 Huntersville. 8. A particle size of the antimicrobial agent is preferably 1-100 nm and wherein the air filter media of claim 1 Huntersville. 9. The mass ratio of the antimicrobial agent in the medium as a whole (=Huntersville content) is less than or equal to 1000 ppm, and greater than or equal 2.0 degrees and bacteriostatic activity, preferably greater than or equal to 2.5 and wherein the antimicrobial air filter media of claim 1. 10. 2 3 Layer structure or the structure of each of the one or more layers of nanofibers of varying diameter, smaller than that of the nanofiber layer to protect the claim 1 characterized in that the air filter media and the antimicrobial. 11. 2 3 Layer structure or the structure of the one or more layers of the nanofibers of the ultrafine fibers by changing the diameter of each of the fibers, the particle size of the collected dust to be separated and the collection efficiency and improve the life characterized in that the antimicrobial air filter media of claim 1 and.