摘要 |
Deep-draw mouldings are produced from needle-felts having a piercing density of 10-300 per sq.cm. and contg. at least 10 wt.% of extensible fibres with breaking extension of at least 100% at 150 deg.C below m.pt. The felt may be treated with a binding agent of thermoplastic or crosslinking type, then is heated to a temp. above 150 deg.C. but below the m.pt. before being deep-drawn. The process gives a uniform, dimensionally-stable moulding partic. suitable for use as a filter element. |