Process for producing wholly aromatic polyamide fibers
US4073837A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 26, 1975 |
| Grant date | Feb 14, 1978 |
| Priority date | — |
| Expiry date | Aug 26, 1995 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P70/62
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A process for producing wholly aromatic polyamide fibers by extruding a spinning solution of a wholly aromatic polyamide in an amide solvent into an aqueous coagulating bath containing inorganic salts, said process comprising feeding an aqueous coagulating liquid containing calcium chloride and having an amide solvent concentration of not more than 3% by weight to the vicinity of a spinneret, flowing the coagulating liquid in said bath at an average velocity not more than 0.1 time the velocity of yarn take-up in the yarn advancing direction, discharging the coagulating liquid having an amide solvent concentration of not less than 4% by weight from said bath, treating the coagulating bath with an organic solvent consisting substantially of methylene chloride, and extracting and recovering the amide solvent from the coagulating liquid.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.