Silk Wax and Certain Physical Properties of Raw Silk

Abstract

The ether-soluble fraction of a series of samples of raw silk has been determined. It has been expressed in terms of the E. S. No., which designates the number of milligrams of ether-soluble material obtainable from a 10 g. sample of silk. The E. S. Numbers of the silks which have been investigated fall between 30 and 100. The average E. S. No. is 55. There exists no apparent relation between the E. S. No. and the nature, boil-off, tenacity, elongation, cohesion and resistance to friction of raw silk. The wetting properties of raw and dewaxed silk have been compared by means of the sinking test. It was found that in general removal of the wax reduces the sinking time from many seconds or even several minutes to a fraction of a second.