Nonwoven Electret Filter Medium for Air Permeability and Filtration Efficiency

The patent applies parameter changes by incorporating nucleating agents that modify the crystallization behavior of the thermoplastic resin during fiber formation. This changes the physical parameters of the fibers (crystal structure, morphology) to create an open network structure with high porosity (≥90%) while maintaining effective filtration through electrostatic charging with charge adjuvants.

The patent uses composite materials by combining thermoplastic resin with charge adjuvants and nucleating agents in a multi-component system. The thermoplastic resin provides the structural framework, the nucleating agents control crystallization to form open structures, and the charge adjuvants provide electrostatic filtration capability, achieving both high air permeability and filtration efficiency.

The patent changes the crystallization parameters of the thermoplastic resin by adding nucleating agents, which control the formation of crystal structures during fiber solidification. This parameter change enables the creation of an open network architecture with high porosity that maintains both filtration efficiency and air permeability, avoiding the need for dense structures.

The patent replaces mechanical filtration (which would require dense structures) with electrostatic filtration using charge adjuvants. The electrostatic field generated by charged fibers captures particles efficiently without requiring physical blockage, thus maintaining high air permeability while achieving effective filtration.

The patent applies preliminary action by incorporating charge adjuvants into the polymer matrix before fiber formation. These charge adjuvants are pre-loaded into the fibers during extrusion, so that the electrostatic charge is already present in the material structure before the nonwoven is formed, eliminating or reducing the need for subsequent corona charging steps.

The patent merges multiple functions into the fiber material itself: the thermoplastic resin provides structural integrity, the nucleating agents control crystal formation, and the charge adjuvants provide electrostatic charging capability. This consolidation of multiple components into a single multifunctional material simplifies the manufacturing process by reducing the number of separate processing steps required.