In 1892, Cross and Bevan patented the preparation of a new and curious compound of cellulose, the thiocarbonate (1) (2) (3). Great hopes were based upon this product at the time of its discovery. It was expected to yield a considerable industrial and financial profit and also to contribute to the scientific study of cellulose. The later patents of C. H. Stearn (4) describe the application of viscose to the spinning of artificial silk. The viscose is projected into solutions of chloride of ammonium and washed in a succession of saline solutions to remove the residual sulphur impurities. The author remarks that though it has a certain interest to have succeeded in making a thread from this compound and thus adding another to the processes existing for this purpose, he is not of opinion that it shows any advance on the lustra-cellulose (2) and (3). He also considers that the bisulphide of carbon, which must be regarded as a noxious compound, is a serious bar to the industrial use of the process, and for economic work he considers that the regeneration of ammonia from the precipitating liquors is necessary and would be as objectionable as the denitration baths in the collodion process. The final product not being on the market he does not pronounce a finally unfavourable opinion.
The author and the Vereinigte Glanzstoff-Fabriken after long investigation have decided to make nothing but the lustra-cellulose (2) and (3). A new factory at Niedermorschweiler, near Mulhouse, is projected for this last production.
BIBLIOGRAPHY
Introduction
(1) Bull. de la Soc. industr. de Mulhouse, 1900.
(2) Réaumur, Mémoire pour servir à l'histoire des insectes, 1874, 1, p. 154.
(3) English Pat. No. 283, Feb. 6, 1855.
(4) Swinburne, Electrician, 18, 28, 1887, p. 256.
(5) Weston (Swinburne), Electrician, 18, 1887, p. 287. Eng. Pat. No. 22866, Sept. 12, 1882.
(6) German Pat. No. 3029. English Pat. No. 161780, April 28, 1884 (Swan).