Patent · US Expired

Gradient density filter medium

US4793923A · kind A · utility

8Cited by
9References
9Claims
0Family size

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Inventors

Key dates

Filing dateJan 15, 1988
Grant dateDec 27, 1988
Priority date
Expiry dateJan 15, 2008

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB01D39/14
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

A filter medium for filtration of a fluid to flow therethrough from an upstream side to a downstream side thereof, said filter medium comprising a substrate having a density gradient wherein the density is high on the upstream side and low on the downstream side of the substrate.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.