Group I | Group II |
P. Rotor spinning | 1. Twistless parallel fibres in core and helically arranged filament on surface |
Q. Air-jet spinning | 2. Helically twisted core and distinct wrappers on surface |
R. Wrap spinning | 3. Multifilament core covered by staple fibres stuck to molten polymer |
S. Bobtex spinning | 4. Twistless core wrapped regularly and helically by thin fibre ribbons |