What is Ultra-fine fiber ? What is Microfiber ? Novelty fibers.

Ultra-fine or microfibers were developed partly because of improved precision in

engineering techniques and better production controls, and partly because of the need for lightweight, soft waterproof fabrics that eliminate the more conventional coating or lamination processes. As yet there are no universal definitions of microfibers. Textile Terms and Definitions simply describes them as fibers or filaments with linear densities of approximately 1.0 dtex or less. Others  have used such terms as fine, extra-fine and micro-fine corresponding to linear densities

ranging from 3.0 dtex to less than 0.1 dtex. They are usually made from polyester and nylon polymers, but other polymers are now being made into micro-fibers. The

Japanese first introduced microfibers in an attempt to reproduce silk-like properties

with the addition of enhanced durability. They are produced by at least three established methods including island-in sea, split process and melt spinning

techniques and appear under brand names such as Mitrelle, Setila, Micrell, Tactel and so on. Once in woven fabric form their fine diameter and tight weave allows up to 30000 filaments cm-2, making them impermeable to water droplets whilst

allowing air and moisture vapor circulation. They can be further processed to enhance other characteristics such as peach-skin and leather-like appearances. The split technique of production imparts sharp-angled edges within the fiber surface,

which act as gentle abraders when made into wiping cloths that are used in the

optical and precision microelectronic industries. Microfibers are also used to

make bacteria barrier fabrics in the medical industries. Their combined effect of low diameter and compact packing also allows efficient and more economical dyeing and finishing.

Finally, constant pressure to achieve and develop even more novel applications

of fibers has led to a number of other and, as yet, niche fibrous products. In principle,

the new ideas usually strive to combine basic functional properties of a textile

material with special needs or attractive effects.

Scanning electron microscope (SEM) micrographs of polymer blend (PB)