| 摘要 |
In apparatus comprising needles (l0), a mandrel (ll) and electrostatically charged plates (l2, l3, l4 and l5), variation of the electrostatic potential on the mandrel (ll) and the plates (l2, l3, l4 and l5) produces variation of the fibrous structure produced. In general, where the mandrel (ll) is significantly more attractive to the fibres, a microstructure of fibres of substantially uniform diameter is produced, these fibres being generally randomly orientated. Where the voltages on the mandrel (ll) and on the plates (l3 and l5) are varied to lessen the attraction of the mandrel (ll) relative to the plates (l3, l5) the fibrous structure is varied to produce fibres of a larger diameter than the original micro fibrous structure, this having a significant effect on characteristics of the fibrous structure. |
