How Viscose is Made
"First, wood pulp is cooked, chemically washed, and pressed into large sheets similar to blotting paper. These sheets are steeped in caustic soda which mercerizes and further refines the cellulose. A shredding process reduces the sheets, now called alkali cellulose, into white crumbs.
Then, carbon disulphide is mixed and turned into orange crumbs cellulose xanthate. Lastly, the orange crumbs are mixed again with a dilute caustic solution. They gradually dissolve into a liquid called viscose that resembles honey. Viscose liquid is filtered and aged to be ready for spinning.
The spinneret is a small thimble shaped nozzle pierced with many tiny holes. The viscose solution is forced through the spinneret into an acid bath which hardens each tiny stream of liquid into a solid filament. The thread with many filaments is wound into a "cake" which are then treated, bleached, washed, then dried. Some "cakes" are wound directly into cones of viscose yarn."
From the American Viscose Corporation.