Back to results
US 5,175,276 AGranted
Process for the production of cellulose ester fibrets
AssigneeHoechst Celanese Corporation
InventorsSamuel S. McNair, Jr., David M. Gault
Life of this patent
Estimating the term…
Abstract
An improved process for the production of cellulose ester fibrets wherein a thickened slurry of the fibrets in a liquid mixture of a solvent for the fibrets and a fibret non-solvent is contacted with saturated steam in the separation of the solvent from the fibrets.
Claims9
A process for the production of fibrillar cellulose ester material, said fibrillar cellulose ester material produced thereby being substantially free of chips and pills, said process comprising the steps of:
- providing a dope comprising a cellulose ester, a solvent for said cellulose ester, and a nonsolvent for said cellulose ester, said solvent and said nonsolvent being miscible;
- attenuating said dope, under conditions of high shear, whereby a slurry of fibrillar cellulose ester material is formed;
- thickening said slurry by removal of a portion of said solvent and said nonsolvent;
- and
- separating said solvent from said thickened slurry by sparging said thickened slurry with saturated steam.
2 more elements
Dependencies are inferred from the claim text.