material filtrante plissável a partir de um material de velo e processo para a produção de um material filtrante plissável.

摘要

A non-woven batt (1), e.g. of 200 g/m 2>, containing drawn synthetic fibers with a thermoplastic or thermosetting binder is heated in an oven (2), e.g. to about 200 [deg]C, and then passed between profiled calender rollers (3), e.g. at 80 to 90 [deg]C, to pleat and cool it. The pleats have grooves to act as spacers, with a height equal to at least a quarter of the material thickness.