Patent · US Expired

Method of making filter paper

US4710402A · kind A · utility

2Cited by

6References

14Claims

0Family size

Inventors

Sune Backman · Djursholm, SE
Hakan Hakanson · Lund, SE

Key dates

Filing date	Sep 4, 1984
Grant date	Dec 1, 1987
Priority date	—
Expiry date	Sep 4, 2004

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.