What are nonwovens?
While the name describes these engineered materials by what they are not, make no mistake, nonwovens play an important and defining role in a wide range of end-use applications.
“Nonwoven” is an interesting term. To most, the word nonwoven means “not a woven” or “not a knit,” but nonwoven fabrics are much more than what they are not.
The Prologue of “Introduction to Nonwovens Technology” provides a historical listing of possible beginnings of nonwovens. These hypothetical beginnings range from legends to early technology developments.
The actual roots of nonwovens may not be clear, but in 1942 the term “nonwoven fabrics” was coined and such fabrics were being produced in the United States of America.
These early “nonwoven fabrics” were created by adhesively bonding fiber webs. The first written definition of nonwoven fabrics came from the American Society for Testing and Materials (ASTM) in 1962, which defined nonwovens as “textile fabrics made of a carded web or a fiber web held together by adhesives”.
Currently, INDA, Association of the Nonwoven Fabrics Industry, defines a nonwoven as “sheet or web structures bonded together by entangling fibers or filaments (and by perforating films) mechanically, thermally or chemically. They are flat, porous sheets that are made directly from separate fibers or from molten plastic or plastic film. They are not made by weaving or knitting and do not require converting the fibers to yarn.”
Technical definitions express the fundamental basis for the nonwoven processes, but due to the wide variety of production techniques, a general description of nonwoven fabrics is not enough. As with woven or knitted fabrics, each process possesses unique characteristics. The resulting fabrics do not have much in common, aside from being categorized as nonwoven. Variables and components in nonwoven materials – such as fiber selection, web formation, bonding and finishing techniques – can be altered to manipulate fabric properties or reverse-engineer fabrics based on functional requirements.
Due to their assortment of achievable characteristics, nonwoven fabrics serve various markets, including medical, apparel, automotive, filtration, construction, geotextiles and personal protective equipment. The flexibility of nonwoven materials in terms of function and application is why the nonwovens industry has established itself as a vibrant and growing market worldwide.