Model-Based Optimization of Electret–Nanofiber Hybrid Multilayer Filters with Stable Performance Under ISO 29463 Discharge Conditions

The continuous miniaturization of semiconductor and lithium-ion battery manufacturing processes has intensified the demand for stringent particulate control in cleanrooms while simultaneously increasing the importance of energy efficiency. However, conventional melt-blown (MB) electret filters suffer from severe filtration efficiency degradation under ISO 29463 discharge conditions, whereas glass fiber filters exhibit an excessive pressure drop. To address this trade-off, in this study we propose an electret–nanofiber hybrid multilayer filter and establish a dual-efficiency model for its systematic optimization. The proposed model integrates the slip flow effect of nanofibers and incorporates a structural resistance factor (β = 0.125) derived from the ultrasonic bonding process. Experimental validation demonstrates that the model achieves high predictive accuracy (R2 = 0.9995), and the optimized hybrid filter maintains > 98.1% filtration efficiency after ISO 29463-5:2022 discharge testing, markedly outperforming conventional MB filters (41.4%). Furthermore, the hybrid filter exhibits a quality factor (QF) of 0.117, more than twice that of commercial glass fiber filters. These findings demonstrate that the proposed model-based framework provides robust design guidelines for next-generation energy-efficient air filtration systems capable of meeting stringent international standards.