The formation of dry, wet, spunlaid and other types of nonwovens

Abstract:

The term ‘nonwoven’ arises from at least half a century ago when these materials were often regarded as low-price substitutes for traditional textiles and were generally made from carded, ‘dry’ fibres on converted textile processing machinery. The nonwovens industry, however, has drawn on the practices and know-how of many other fields of materials manufacturing, with a piratical disregard and an eye to the most diverse range of end-use products. Today, it would be reluctant to be associated with the conventional textile industry and its commodity associations. The nonwoven technologies originating from the textile industry manipulate fibres in the dry state. Paper-based nonwoven fabrics, meanwhile, are manufactured with machinery designed to manipulate short fibres suspended in fluid and referred to as ‘wetlaid’. ‘Spunlaid’ nonwovens – spunbond, meltblown, apertured films and the many layered combinations of these products – are manufactured with machinery developed from polymer extrusion, with the fibre structures simultaneously formed from molten filaments and manipulated like plastics. This chapter examines the various bonding processes for producing nonwovens.