Abstract
It was found that commercial filter papers contained appreciable amount of organic solvent extractable, non-volatile substances (abbreviated as impurities).
The contents and some chemical properties of the impurities obtained from several kinds of commercial filter paper products were examined by means of gravimetric analysis, thin-layer chromatography, gas liquid chromatography and infra-red spectroscopy.
There were about 0.040.08 weight per cent impurities (a filter paper piece of 9cm diam. contains about 200400μg impurities), whose major components were complex mixture of C16C33 saturated and unsaturated hydrocarbon having straight and branched structures.
