igos] Wheeler — Problems in Cellulose Field. ill 



ing what truth there may be in each one. The attempts to 

 hold to one theory have been attended with serious difficul- 

 ties. As for cellulose (cotton and linen fabrics) its nature as 

 a chemical compound comes into play in certain dyeing- pro- 

 cesses. It behaves as a weak acid and if this acid character 

 is increased by conversion into oxycellulose, it exhibits an 

 increased affinity for basic dyes. On the other hand, Vignon 

 has caused cotton by treatment with ammonia under various 

 conditions to take up as much as 2.86 per cent, N which is 

 not extracted by dilute hydrochloric acid and now, possessing 

 basic properties, it will take an acid dye from an acid bath. 

 These reactions seem to be cases of simple salt formation. As 

 for the solid solution theory Witt regards substantive dyeing 

 as a case of one solid dissolving another. The dye, being 

 more soluble in the fibre than in the water, is extracted there- 

 from by the fibre and in the fibre the dye exhibits the same 

 characteristics which it shows in aqueous solution. Accord- 

 ing to this view the chemical nature of the textile is of no 

 consequence except as it affects its solvent capacity. The 

 behavior of cellulose with certain dyes does not seem to mili- 

 tate against this view. The general question is constantly 

 under investigation. 



Although cellulose is distinguished by its permanence, it is 

 attacked by a great variety of oxidizing agents. The pro- 

 duct, called oxycellulose, is not uniform in character and 

 experimenters seldom agree in their analytical data. Bumcke 

 and Wolffenstein recently discarded the term oxycellulose and 

 re-opened the whole question. The action of hydrogen perox- 

 ide upon filter paper was studied. They came to the conclu- 

 sion that cellulose can not undergo simple oxidation without 

 hydrolysis. They substitute the name hydracellulose for 

 oxycellulose, this name indicating the hydrolytic production 

 and aldehydic properties of the product. It bears the same 

 relation to cellulose as glucose to cane sugar. Tollens has 

 also recently investigated the oxycellulose and proposes the 



