US 11,668,024 B2
Polar solvent solution and production method thereof
Kana Ishida, Yamagata (JP); Hironori Yamamoto, Yamagata (JP); Hiroaki Suzumura, Yamagata (JP); and Kazuhide Sekiyama, Yamagata (JP)
Assigned to SPIBER, INC., Yamagata (JP)
Filed by SPIBER INC., Tsuruoka (JP)
Filed on Jan. 10, 2020, as Appl. No. 16/740,106.
Application 16/740,106 is a division of application No. 15/564,142, abandoned, previously published as PCT/JP2016/061025, filed on Apr. 4, 2016.
Claims priority of application No. 2015-080226 (JP), filed on Apr. 9, 2015.
Prior Publication US 2020/0131671 A1, Apr. 30, 2020
Int. Cl. D01F 4/02 (2006.01); D01C 3/00 (2006.01); C07K 14/435 (2006.01); D01F 1/02 (2006.01)
CPC D01F 4/02 (2013.01) [C07K 14/435 (2013.01); C07K 14/43518 (2013.01); D01C 3/00 (2013.01); D01F 1/02 (2013.01)] 12 Claims
OG exemplary drawing
 
1. A method for producing a polar solvent solution in which a solute containing a polyamino acid is dissolved in a polar solvent, comprising:
changing a water content of the solution to adjust the viscosity of the solution,
wherein the solution has a water content of less than 5% by mass based on 100% by mass of the solution, and
the polar solvent comprises at least one selected from the group consisting of dimethylsulfoxide (DMSO), N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMA), and N-methyl-2-pyrrolidone (NMP).