“Conventionally, in the manufacture of cellulose ester filaments, the cellulose ester polymer is dissolved into a solvent, that solution is known as dope. The dope is pumped to a die (or jet or spinneret) having a plurality of holes therethrough. The die is typically located at the upper end of a spinning cabinet. When the dope exits the die, the solvent flashes from the dope and the filaments begin to solidify. While the filaments travel downwardly through the cabinet, the solvent is captured within the cabinet for reuse. At the bottom of the cabinet, there is an outlet through which the filaments exit the cabinet. Typically, the filaments are guided from their downward (or vertical) travel to a generally horizontal direction (including angles below the horizontal) of travel at the outlet of the cabinet. The guide may be any conventional guide device, but it does not lubricate the filaments as their direction is changed. Thereafter, the filaments exit the cabinet. After exit, the filaments are lubricated by a lubricator, for example, a kiss roll. This lubricator is typically located about 6-12 inches (15-30 cm) from the exit of the cabinet. Then, the filaments are drawn away by a feed roll.”  (Clarkson et al, US Patent 7,815,832; 10/19/2010)

Processing    
Solution Spinning  
Spinning   

Recent US Patents

Comments