An electrostatically charged non-woven filter media based on polyproplyene resins was obtained from a spray-spinning extrusion system, which was equipped with a corona discharging unit. The effect of electrostatic characteristics of the media on the filtration performance was investigated. effective surface charge density (ESCD) of the filter media was measured using a vibrating electrode technique, and it was shown that the highest value achieved was at 200 μA of the corona current. The measured filtration efficiency using a filter tester showed that the electrostatically charged filter media had an excellent filtration efficiency compared to the uncharged filter media. This resulted from the particlecollection ability that was generated by the electric field of the filter media. Throughout the experimental results the filtration efficiency was shown to be strongly dependent on ESCD of the filter media. The filter media can be used as a highly effective filter for air purification systems.

코로나방전(corona discharging) 장치가 장착된 공압출방사(spray-spinning extrusion) 시스템을 이용하여 정전기(static electricity)를 부여한 폴리프로필렌(polypropylene, PP) 부직포 여과재(filter media)를 제조하여 여과특성에 미치는 영향을 조사하였다. 제조한 폴리프로필렌 부직포 여과재에 잔존하는 표면전하밀도(effective surface charge density, ESCD)를 진동전극기술(vibrating electrode technique)을 사용하여 측정하였는데, 코로나 전류가 증가함에 따라 폴리프로필렌 부직포 여과재의 표면전하밀도는 증가하였으며 200μA에서 최대치를 나타내었다. 필터성능시험기를 사용하여 여과효율을 측정한 결과, 정전기가 부여된 폴리프로필렌 부직포 여과재는 정전기가 부여되지 않은 경우보다 매우 우수한 여과효율을 나타내었다. 이는 여과재에 존재하는 전기장(electric field)에 의한 입자포집률의 증가에 기인된다. 실험 결과, 표면전하밀도와 여과효율은 밀접한 관계가 있는 것으로 나타났으며 정전기가 부여된 폴리프로필렌 부직포 여과재는 우수한 여과특성을 가짐으로써 공기조화용 에어필터 소재로 사용이 가능하다.