Abstract
The multilaid composite nonwovens have been utilized widely in geotextile fields for soil reinforcement and water drainage. In this study, the spunbond and needle-punched nonwovens made from polypropylene(PP) and polyethylene terephthalate(PET) fibers were assembled with different horn pressure and speed of anvil roller in an ultrasonic bonding system, to produce the multilaid composite nonwovens like combinations of spunbond/spunbond or spunbond/needle-punched nonwovens. Dimensional changes and tensile properties of the produce nonwovens were evaluated under different experimental conditions. Also, to understand the drainage capability of the composite nonwovens, their transmissivity characteristics for liquid media were investigated with a newly designed appartus. As the result, the maximum transmissivity was obtained at the three layer composite nonwovens composed of PP spunbonds on both sides and PET needle-punched nonwoven incenter layer.