초록 ▼

A filter is composed of filter media having the following characteristics in combination: a) the filter media has a greater affinity for the filtered fluid than for contaminants in the fluid, and wherein the work of adhesion between the filter media and the contaminants is less than the work of adhe

A filter is composed of filter media having the following characteristics in combination: a) the filter media has a greater affinity for the filtered fluid than for contaminants in the fluid, and wherein the work of adhesion between the filter media and the contaminants is less than the work of adhesion between the filter media and fluid, and wherein the filter media is preferentially wetted by the fluid relative to the contaminants; b) the filter media is composed of fibers having a defined surface area ratio facilitating fewer attachment sites for contaminants, and, in the case of cleanable reusable filters, facilitating cleansing backwash of the cleanable reusable filter by cleansing fluid along a reverse flow backflush path; c) the filter media has a thickness of 0.025 to 0.075 inch, 0.7 to 2.0 millimeters; d) the face area of the filter media is maximized by pleating the filter media and forming the pleated filter media into an annulus having an inner circumference and an outer circumference and having at least five pleats per inch along the inner circumference; e) the filter media is optionally provided with both upstream and downstream support layers preventing collapse of the thin surface filter media during both filtration and backwash, the support layers being pleated annular screens sandwiching the pleated filter media therebetween, the inner portions of the pleats of the downstream support layer screen adjacent the inner circumference preventing blinding.

대표청구항 ▼

1. A fluid filter element for filtering contaminants in fluid flowing therethrough comprising filter media having a greater affinity for said fluid than for said contaminants, wherein said filter media is characterized by the following conditions in combination:a) said filter media has a greater aff

1. A fluid filter element for filtering contaminants in fluid flowing therethrough comprising filter media having a greater affinity for said fluid than for said contaminants, wherein said filter media is characterized by the following conditions in combination:a) said filter media has a greater affinity for said fluid than for said contaminants; b) the work of adhesion between said filter media and said contaminants is less than the work of adhesion between said filter media and said fluid, wherein said filter media is composed of fibers having a defined surface area ratio less than ten, said defined surface area ratio being the ratio of actual surface area of said fiber to the theoretical minimum surface area of said fiber, said defined ratio minimizing the number of attachment sites for said contaminants.