Patent · US Expired

Filter paper for an edge-type filter

US4810380A · kind A · utility

2Cited by
11References
3Claims
0Family size

Inventors

Key dates

Filing dateMay 6, 1987
Grant dateMar 7, 1989
Priority date
Expiry dateMay 6, 2007

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T156/1052
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

A flat annular disc filter paper has a plurality of randomly oriented fibers at its surface. The paper is impregnated with a phenolic resin so as to resist compression of the disc and swelling of the paper. The filter paper is made by soaking the paper in the resin, heating the paper and resin so as to burn and melt the resin into close contact with the paper and rolling the filter paper at a temperature above ambient temperature.

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