The author studied the causes of uneven dyeing of viscose silk and arrived at the following conclusions;
1. The viscose silk is dyed good when the cellulose is acted strongly by alkali. The long ageing of alkali cellulose, the large content of alkali in viscose, the long ripening of viscose and the treatment of silk with alkali make the fixation of dyes good.
2. The viscose silk is dyed good when the cellulose is not acted strongly by acid. The viscose silk is dyed good when the acid is completely eliminated in the centrifugal spinning or the second bath is used in the bobin spinning or the acidity of coagulation bath is not strong. When the cellulose is acted strongly by acid, the dyeing is not good.
3. The composition of the coagulating bath affects the dyeing property of the viscose silk. The bath consisting of sodium salt as main component gives the best dyeing result, and as other metals than sodium is used the dyeing becomes bad.
4. The method of spinning affects the dyeing. The centrifugal spinning gives a silk of a better dyeing quality than the bobin spinning, and the stretch spinning as well as the high speed spinning give a silk of worse dyeing quality. The finer thread is generally of bad dyeing property.
5. The viscose silks of different mills are of different dyeing quality.

View full abstract