Filter Media Surface Modification for Enhanced Sealing and Apparatus Utilizing the Same

Abstract

A novel surface treatment is provided for portions of filter media coming in contact with the filter media holder, such as filter housing. In certain applications, the treatment is also applied to the filter media holder, depending on the application. Filter media having at least two distinct surface property modifications are provided in liquid filtration applications to enhance the performance of a filtration system, reduce the cost of the system, provided a visual means of detecting fluid bypass, and minimize fluid holdup volume within the filter media, all with substantially no loss of performance performances parameters, even in steam sterilization applications.

It is claimed: 
     
         1 . An apparatus for filtering fluid, the fluid being received into the apparatus from a fluid container placed in fluid communication with an inlet port on the apparatus, the fluid passing through a tubular porous filter element contained within the housing, and the filtered fluid exiting the apparatus through an outlet port being in flow communication with a fluid receiving container, said apparatus comprising:
 a. A housing comprising:
 i. a filter bowl sealed to a filter head, forming a chamber, an inlet port and an outlet port located on the filter head, the inlet port in fluid communication with the atmosphere at one end thereof and the chamber at the other end thereof, the outlet port in fluid communication with the atmosphere at one end thereof and the chamber at the other end thereof; 
 ii. an end cap within the chamber attached to the filter head for holding a tubular filter in a sealing relationship with the filter head and the end cap, the end cap having an outer upstanding peripheral wall and an inner upstanding peripheral wall, the inner upstanding peripheral wall spaced inwardly a predetermined distance from the outer upstanding peripheral wall; 
 iii. a tubular filter element within said chamber, the tubular filter element having an upper end and a lower end, the upper end sealed to said filter head, and the lower end sealed between the outer upstanding peripheral wall and the inner upstanding peripheral wall of filter end cap, wherein at least one portion of the tubular filter element adjacent the filter head, or the inner upstanding peripheral wall, or the outer upstanding peripheral wall, of the end cap is treated to modify the surface properties of the fibers comprising the tubular filter element, thereby causing the tubular filter element to be liquiphobic at the at least one treated portion.