METHOD OF DISSOLVING CELLULOSE ACETATE

摘要

PURPOSE:To produce a cellulose acetate dope which has a high concentration with a low insoluble content and does not corrode metal even when in contact therewith over a prolonged time CONSTITUTION:A mixture of cellulose triacetate and a solvent is introduced into a dissolver 1 and stirred at ordinary pressure and 35 deg.C for 60min to thereby prepare a solution (a) in which the solid has been dissolved incompletely and which has a viscosity of 640 P at 35 deg.C. The solution (a) is then heated and pressurized with a heat exchanger 3 for heating at a predetermined temp. to completely dissolve the solid. The resulting solution (b) is fed to a heat exchanger 4 for cooling, where it is cooled to 35 deg.C. The solution (b) in this state is sent from the exchanger 4. This solution (b) has a viscosity lower than that of the solution (a) by 2 to 11% of the latter viscosity.