Filter leaf.

摘要

A filter leaf is disclosed which is particularly suitable for supporting a layer of a fibrous or particulate filter material such as diatomaceous earth, among others. The leaf comprises a pair of fine mesh filter screens (30) positioned on opposite sides of a system of backing sheets (24) and a drainage screen (20) which are framed by a member (12) to which the fine mesh screens are continuously bonded. The arrangement enables the fine mesh screens (30) to be stretched and tensioned such that the particulate or fibrous material does not migrate and form cracks during filtering.