Patterned Nanofiber Filtration Medium via Electrostatic Deposition

The patent applies local quality by creating patterned nanofiber regions with different spatial distributions on the substrate. The electrospinning process deposits nanofibers in specific patterns (e.g., radial, concentric, or random patterns) that optimize filtration performance in different zones, allowing submicron fibers to be strategically positioned where they provide maximum filtration efficiency while maintaining acceptable pressure drop characteristics.

The patent transitions from conventional three-dimensional bulk filter media to two-dimensional patterned nanofiber assemblies on flat substrates. This dimensional change allows for precise control of fiber spatial distribution and density, enabling optimization of the figure of merit by arranging submicron fibers in patterns that maximize particle capture efficiency while minimizing airflow resistance.

The patent uses a substrate as an intermediary carrier that supports the fragile electrospun nanofibers during and after the electrospinning process. The substrate provides mechanical strength and structural integrity, allowing the handling of submicron fiber assemblies without direct manipulation of the individual fragile fibers, thus solving the handling difficulty while maintaining the small fiber diameter benefit.

The patent creates a composite structure combining electrospun nanofibers with a substrate material. This composite approach integrates the high surface area and filtration efficiency of submicron nanofibers with the mechanical robustness of the substrate, resulting in a material that retains the filtration advantages of small fiber diameters while overcoming the fragility and handling issues of standalone nanofiber mats.