US866768A - Process for the manufacture of artificial silk filaments from nitrocellulose. - Google Patents

Description

percentatge'ot water.

, UNIJFEI) STATES PATENT QFFliQE.

CHARLES BOT'ILER, QF JULIGH, GERMANY, liSSlGNOR TO KUNST'FADEN GESELLSOHAFT MIT BESQHRAlXKTER llAF'lUNG, OF JULlUl-l, GERMANY, A CORPORATION.

PROCESS FORTHE MANUFACTURE OF ARTIFICIAL SILK FILATKENTS NITBOCELLULOSE.

Specification of Letters Patent.

Patented Sept. 2d, 19%.

Application filed December 4,1906. Serial N01 346,21

To all whom it may concern:

Be it knownthat I, CHARLES Bowman, a subject of the German Emperor, an d a resident of .liilich, Germany, have invented a. certain new and useful Improved Process for the Manufacture of A rtilicial Silk Filaments lrom Nitrocellulose, and i do hereby declare the following to be a lull, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to letters of reference marked thereon, which form a part of this specification.

My invention relates to the art of manufacturing socalled artificial silk or artificial sill: filaments from nitrocellulose is comparatively new and of late years particularly has been in a state of active development. An important point or progressive knowledge forming a part of the observations necessary in considering such manufacture consists in the observation or determination of at what .moisture contents the nitrocellulose which serves as the starting or base material can be most advantageously brought into solution with the view of producin therefrom as perfect an artificial silk as possible. The investigations made in this domain have found their expression in a number of Letters Patent and applications for Letters Patent each of which has had [or object to obtain protection for the use in the manufacture under notice of nitrocellulose containing a dolinite In this connection are concerned the folloWing:-l. The specification accompanying an application for Letters Patent in Germany made by J. Dongs, of liesancon France, No. B11841, Class 29b, describing the use of nitrocellulose having from 6% to 10% water content. The specification accompanying aniapplication l'or Letters Patent in Germany made by Johann Stoerck, of Brussels, Belgium, No. Stjflllfj, Class 2910, describing the use of nitrocellulose having frj0ml2% to 20% water content. 3. The specification oi German Letters Patent granted to llilaire do Chardonnet, of Paris, France, No. 81599, describing the use of nitrocellulose havingfrom 25% to 30 it wiuiorcontcnt. 4.

est and clearest solution possible in the known solvents, as well as in respect of the further working up of the collodion solution obtained in this way and of the final product thereby obtained into artificial silk, lies between 20 and 25 per cent.

Departing from the methods described in the specilications hereinbefore mentioned, it is found dil advantageous to carry out drying by presses, in a current or air or by heat, as is necessary where the water content is below 20 9?; It is also found that by a single whirling in a centrifugal machine the water contentef the nitrated cotton coming from the washing machines can only be reduced down to awater content 01' about 25% so in carrying out the improved method, while observing the rules laid down by practice, the once whirled nitratcd cotton is introduced in smallportions into a second and thence into a third and if necessaryinto a fourth centriiugal machine and in this way, by keeping time accurately to seconds, a regular abatcnien t of the water coutcnt within the limits of a few per cent. is successfully obtained. The nitrated cotton prepared in this careful Way and in contradislinction to previous experience and observation canin all cases be brought to an easy and clear solution which filters excellently Well. The solution takes place in closed vessels in the proportion of 18 to 23 kilos, dry weight, of nitraicd cotton to lOQ liters of solvent, consisting of a mixture of alcohol and ether in the proportions of 352 or 111; this is however only an example. Other relative proportions of weight and measurement, as well as mixtures of other known solvents such as methyl alcohol, acetone etc., may how ever be employed.

The most important advantage however of the collodion solution prepared from a nitrocellulose with a water content 01 21 to 24 per cent. consists in addition to the advantages stated in its capability oi being easily and regularly spun and its simplified denitrati on in the obtaining of a final product which is characterized by special strength of filament and increased brilliancy especially in a dyed condition.

What I claim is:-

.l. The herein described process for the manufacture of artificial silk which consists in treating nitrocellulose to reduce the water content tliereoF-to from 21 to 24 per cent.

and addinga solvent therctoto form a collodion solution.

collodlon solution by dissolving said nitrocellulose in a mixartificial silk which consists in reducing the water cou- 15 ture of alcohol and ether or the like.

3. 'llieiierein described process for the manufacture of artificial silk which consists in suhjccting nitrocellulose to centrifugal action to reduce the water content thereof, to

" from 2]. to 24 per cent. and in mixing the sznne with :1

tent of nitrocellulose by subjecting the same to successive centrifugal actions for predeterminedintervals of time.

In testimony whereof, I have signed my name to this specification, in the prcsence of two subscribing witnesses.

CHARLES BOTTLER. Witnesses Bnssin L. Dunning LOUIS VAMnonY.