Para-aromatic polyamide yarn having low filament linear density and a process for manufacturing same
US5882791A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 5, 1997 |
| Grant date | Mar 16, 1999 |
| Priority date | — |
| Expiry date | Aug 5, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/2969
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A p-aramid microfilament yarn and a process for manufacturing the same. In the p-aramid yarn, which has a yarn linear density of at least 300 dtex, comprising a bundle of filaments with a linear density of less than 0.8 dtex, the g value is higher than 2.5 GPa, the elongation (EAB) is higher than 3.4%, and the L002 value is higher than 350 .ANG.. More particularly, the filament linear density is 0.3 to 0.8. The yarn according to the invention has surprisingly favorable properties, such as a high internal shear modulus. The invention also pertains to a process for manufacturing such a microfilament yarn in which p-aramid is subjected to an air gap-wet spinning process of the known type, in which the draw ratio in the air gap combined with the diameter of the capillaries through which the polymer is extruded ensures that microfilament yarn having the desired properties is obtained.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.