Fibers and shapes

Fiber

An individual fine, hair like structure, with a high ratio of length to width. Differences result from their different chemical compositions, the arrangement of their molecules and their external features.

Fiber Longitudinal Configuration

Can be straight, twisted, coiled or crimped. Cotton is naturally twisted and nylon is fairly straight. These effect the various performance properties such as resilience, elasticity, and abrasion resistance.

Fiber Length

Can vary from less than 1" to miles in length. Staple fibers are measured in inches, filament fibers are the longer length fibers. Natural fibers are the length they can be grown where as manufactured fibers can be as long as wished.

Properties of Fibers

Determined by the fibers: Composition and Origin Length and diameter Shape/Cross section form Contour/Longitudinal form Spinnability/Cohesiveness Light Reflecting Qualities Dyeablity

Fiber Surface

Fiber surface affects such properties as hand, luster and wicking. Surface can be smooth, rough, slightly grooved, deeply channeled or wrinkled. Wool fiber is scaly , cotton is smooth, rayon is serrated.

Cotton (not mercerized)

Fibers longitudinal twist, cross section kidney bean shape

Fabric Shape and Light

Flat surface fiber has more luster than a round one A round fiber reflects light in one general direction causing a shiny surface A multi-lobal shaped fiber tends to scatter light causing a diffused glow with sparkle An irregular cross section scatters light in many directions resulting in a dullish appearance with few highlights

Spinnerette

For the creation of manufactured fibers. It is the device used to form the filament, similar to a shower head that the chemicals pass through.

Fiber Characteristics affecting Fabric

Multiple properties and inherent characteristics of the fiber will affect the fabrics: Performance expectations hand or feel Body or weight appearance surface texture luster care end use

Wool

Oval to round, overlapping scales

Crimp

Refers to the bends and twist along the length of the fiber. Greater Crimp increases resilience, bulk, warmth, elongation, absorbency, skin comfort, hand become harsher, luster is reduced. Inherent in wool fibers. Not inherent in manufactured fibers but can be added.

Fiber Diameter

Refers to the thickness of the fibers. Thicker fibers result in greater stiffness which improves wrinkle resistance but can also result in an undesirable roughness. Large diameter fibers result in bulkier fabrics. Fine diameter fibers can result in fabric that is sheer, light weight and generally more drapeable and softer to the touch. Natural fibers vary in diameter where as manufactured fibers are uniform.

Nylon

Round rod shaped is Nylon Bright Triangle shape is Nylon (high modification ratio)

Fiber Selection

Selecting one fiber over the other to produce yarn or fabric depends on: Individual characteristics positive vs Negative qualities Performance expectations appearance, feel, hand and texture desired Drapablity qualities Finishing processes weight or opacity care performance end use fiber's availability Cost

Natural Fibers

Those found in nature: Broken into two categories Protein: Silks and Wools and Cellulose: Seed and Bast

Manufactured Fibers

Those manufactured through the use of science and technology. Also called man made fibers. Three categories: Manufactured Cellulose: Rayons (bamboo and lyocell) , Manufactured Protein: Soy and Manufactured Mineral: Metallic and Glass. Synthetics is the other category of man made fibers that includes Nylon and Polyester.

Fiber Shape

When viewed with the naked eye all fibers look similar, must be seen under a microscope. Microscopic cross sectional shape of the fiber and surface construction determine the bulk, texture, luster and hand of the fiber. These in turn effect the performance properties and end use.

Yarn

Yarn is when fibers are usually grouped and twisted together into a continuous strand. Yarns are used to make various textile materials (woven, or knitted fabric, lace etc)

Flax

bamboo shaped cross sectional view round with hollow section in center

Acetate

lines going vertical, shape is lobular

Cotton (Mercerized)

not as twisted, and cross section is more rounded than the kidney bean shape of not mercerized cotton

Polyester

round fibers both in longitudinal and cross section

Permanently crimped Lyocell

slightly oval