PURIFIED TEXTILE INSULATION 



245 



the purifying process consists in a thorough washing with water. 

 In effect, this is the case. The process, however, for both silk and 

 cotton, being based on substantially complete removal of the ionically 

 conducting salts, especially those of sodium and potassium, prescribes 

 the use of water of low saline content. It also means that the washing 



!i:> 95 

 '<Q 85 

 (Xd 75 

 5^ 65 



3 4 5 6 7 

 TIME IN DAYS 



Fig. 1 — Typical d.c. resistance characteristics of washed and unwashed silk and 

 cotton threads of equal size. 



is best accomplished by a continual flow which after passing through 

 the textile is considered to be contaminated and is not used again. 



Where cotton is to be dyed and washed, the washing consists in an 

 additional operation applied to the cotton immediately following the 

 dyeing operation without the necessity of drying between processes. 



