Method of producing precursor fiber for carbon fiber and carbon fiber
US11932971B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 24, 2019 |
| Grant date | Mar 19, 2024 |
| Priority date | — |
| Expiry date | Dec 10, 2040 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD01F9/328
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A method of producing a precursor fiber for carbon fiber includes extruding a polyacrylonitrile copolymer solution from a spinneret into the air, immersing it in a coagulation bath liquid stored in a coagulation bath, redirecting traveling of the coagulating fiber bundle by a first guide immersed in the coagulation bath disposed below the spinneret, and pulling it out of the coagulation bath liquid into the air to prepare a coagulated fiber bundle, which is then subjected to at least a washing step in water, stretching step, oil agent applying step, and drying step, wherein the depth-directional coagulation bath immersion length, which means a distance between the starting point of the immersion of the spinning dope solution in the coagulation bath liquid and the first guide immersed in the coagulation bath where traveling of the coagulating fiber bundle is redirected, is 3 to 40 cm.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.