Textile fibers have been used to make cloth for several thousand years. First manufactured fiber was produced commercially on 1885 and was produced from fibers of plants and animals. Wool, flax, cotton and silk were commonly used textile fibers. Textile fibers are characterized by the flexibility, fineness and large length in relation to the maximum transverse dimension. On the basis of origin fibers can be classified broadly into three types:

General properties with regard to fiber properties

The general considerations provide the background information upon which the explanations of a fiber’s properties are based.

Fiber-morphology

Morphology or physical structure of textile fiber includes the study of the size, shape and structure of textile fiber, by observing the fiber using a microscope and the relationship between these properties. Fiber’s morphology influences fabric characteristics and performance and the process that will be used in producing a finished fabric.

Fibers or filaments finer than about 10μm tend to become too delicate or fragile for ready conversion into a yarn structure. Fibers or filaments exceeding about 50μm in thickness easily give a yarn structure which is too coarse and too thick for comfort when used as apparel.

Fiber diameter decides a fabric’s performance and hand (how it feels). Large diameter fibers are crisp, rough and stiff. Fine fibers are soft and pliable and fabric made of them drape more easily. In natural fibers, fineness is one factor which determines fine quality fibers of better quality. Fineness is measured in micrometers (a micrometer is 1/1000 millimeter or 1/25,400 inch). The diameter range for natural fibers is 16 to 20 micrometers for cotton, 12 to 16 for flax, 10 to 50 for wool, and 11 to 12 micrometers for silk.

This ratio decides suitability of a fiber for spinning into yarn, provided, it first meets the fiber length and thickness requirement. The smallest appropriate ratio of fiber length to fiber breadth (thickness) is about 350:1. Ratio less than this indicate a fiber which will not permit twisting of fiber into a yarn structure. But fiber ratio of 1000:1 or more spins into a useful yarn. Fineness of manufactured fibers is measured as denier or tex.

Textile fibers range from 1 to 7 denier. Carpet fibers ranges from 15 to 24 denier. Industrial fibers show the broad range from 5 to several thousand, depending on the use. Denier per filament (dpf) describes fiber size; it is often used when describing or specifying yarns. Dpf is calculated by dividing the yarn size by the number of filaments: 80 denier yarn/ 20 filaments equals to 4 denier per filament. Fine cotton, wool has 5 to 8 denier; carpet wool is 15 denier.

White or colorless fibers and filaments are preferred. Color of natural fibers and delustred man-made fibers are white to off-white. Bright-lustre man-made fibers and filaments are colorless because they are translucent. Reason of preference for white or colorless fibers is they can be dyed or printed with any hue of color.

A translucent fiber will transmit light but is not transparent. Silk and manmade fibers, when bright-lustred, are translucent. Cotton, flax and wool are also delustred man-made fibers, tend to be opaque; but when these fibers are made into light to very light weight fabrics, then their fineness makes them translucent.

Luster results from the way light is reflected from surface. This is a subjective measure of the reflection of incident light from a fiber, filament or textile material. The more lustrous a fiber, the more evenly does it reflect the incident light. The less lustrous or dull fiber or filament, the less evenly does it reflect or the more does it scatter the incident light. Cotton has a convoluted fiber structure and wool a serrated surface structure, the result is that these fibers scatter the incident light, and are thus dull fibers. The more regular and even surface structure of flax, mercerized cotton and silk gives these fibers a distinct luster, due to the even reflection of incident light. The irregular specks of delustering agent contained within delusterd man-made fibers scatter sufficient of the incident light to make these fibers or filaments duller than their bright luster equivalents. A preference for non-lustrous or dull textile fibers and filaments exists. This is evident in the predominance of dull-lusterd or non-lustrous apparel and household textiles normally purchased and used by consumers. Cross-section of fiber effects upon luster and other physical fiber properties.