FILTER STRUCTURE WITH ENHANCED DIRT HOLDING CAPACITY

To provide a fluid filtration device incorporating a composite media filter structure capable of removing relatively large contaminants and particles, and a manufacturing method.SOLUTION: A fluid filtration device contains a composite filter media having a coarse porous polymeric nonwoven interlayer (25) located between first (26) and second (28) polymeric fiber-containing filter mats. The fibers in the first and second filter mats are electrospun nanofibers and have diameters different from each other, and each filter mat has a different pore size rating. The interlayer has a coarser pore size compared to one of the first and second filter mats, such that the resulting composite media has an increased dirt holding capacity compared to filter layers that are layered directly on each other without the presence of a coarse interlayer therebetween.SELECTED DRAWING: Figure 1A 【課題】比較的大きな汚染物質および粒子を除去することができる複合媒体フィルタ構造を組み込んだ流体濾過装置および製造方法の提供。【解決手段】第１（２６）および第２（２８）のポリマー繊維含有フィルタマットの間に配置された粗い多孔質ポリマー不織中間層（２５）を有する複合フィルタ媒体を含む流体濾過装置で、第１および第２のフィルタマットの繊維は電界紡糸されたナノ繊維で直径が互いに異なり、各フィルタマットは異なる細孔径等級を有し、中間層は第１または第２のフィルタマットのいずれかと比較して粗い細孔径を有し、粗い中間層が存在しないで互いに直接積層されたフィルタ層と比較して汚れ保持容量が増加した複合媒体を有する流体濾過装置。【選択図】図１Ａ