Taking into consideration the general properties of textile fiber we can mostly divide into two fairly loose properties, physical & chemical main physical properties of textile fibers are properties. The discussed below.
Length: One of the most important properties of textile fiber which determine their spin ability and commercial utility is their length may vary from 5 inch to unlimited length. A spinner or buyer is very much concerned about the average length of fiber, which is also called staple length, referred to as the evenness of a staple or effective length. The fibers staple length more than 100 mm is long staple. 50-100 m.m is medium staple &less than 50 mm is called short staple. Higher the staple length betters the fiber quality. Due to following reasons fiber length is very important.
Yarn strength: The strength of yarn is partly governed by the length of fiber. Longer the fiber finer the yarn, longer the fiber stronger the yarn and longer the fiber less the twist required
Processing: All fibers can’t be process in one type of spinning m/c. As because spinning machines (m/c) are designed on the basis of fiber length. For this reason fiber length is important considering the type of spinning m/c.
Appearance: Appearance of a yarn is also dependent on the length of fiber. Too short fiber will produce a hairy yarn whereas long fiber will produce a smooth surfaced yarn. Moreover for the same count of yarn production, short fiber produces thicker yarn than long fiber.
Fiber Fineness: Fiber fineness is very important in determining the quality and commercial value of fibers. A short fine fiber is more valuable than a coarse long fiber generally fine fibers are long staple. For textile raw material in general, the transverse fiber dimension are of the utmost technical importance, not only in one but in many contexts. Some important reasons of importance of fiber fineness is discussed below.
Stiffness, handle & drape of fibers: It still remains true that as fineness varies and other things are equal, resistance 10 bending changes more rapidly than does fiber- weight per unit length (fineness). For a yarn of given count or a fabric of given w/unit area, made from a given type of material. the resistance to bending diminishes as the fineness of the fiber increases. Fiber fineness is thus an important factor in determining the stiffness of a fabric i.e. softness of handle. Shown are in following table and its draping quality. A summary of the statement is
General Properties of Textile Fiber
Torsional rigidity: As fineness varies and other things are equal resistant too, varies. Hence fineness plays an important part in determining the ease with which fibers can be twisted together during van formation. It can influence with which fibers can be twisted together during yarn formation. It can be shown that the torque generated in a yarn of given count by a given amount of twist increases as the linear density of the fiber increases.
Reflection of light: The finer the fibers in a fabric the greater the number of individual reflecting surfaces per unit area of the fabric. Hence, fabric produced from finer fiber will be more lusterous than the fabric produced from coarser fibers. Fiber fineness thus affects the character of the luster of the fabric.
Absorption of liquid & vapour: Time takes shorter to absorb water or vapour for fine Fibrous material than the coarse fibrous material. This property of material is important in dyeing printing finishing treatment and suitability of breathable fabric wearing property.
Fiber cohesion & twist: In a spun yarn fiber cohesion depends on inter fiber friction developed as a result of twist the finer the fiber the less the amount of twist necessary to prevent the occurrence of slippage. Shape of fiber surface & length of fiber has also part in this respect.
Yarn uniformity: The uniformity of a yarn is largely determined by the average number of fibers in its X-section For a given yarn count. Therefore, the finer the fibers the more uniform the yarn Uniformity of yarn influences the yarn strength, extensibility, luster, fewer end breakage in different stages of processing
Yarn count: There should be a minimum number of fibers in a yarn cross section e.g. worsted >= 40 fibers/x section, cotton >= 80 fibers/x section. For this reason finer yarn are produced from fine fibers but from coarse fiber finer count yarn can’t be produced for an acceptable yarn performance.
Yarn strength: For a particular count of yarn produced from coarse fiber shall have less strength than the fine fibers yarn. It is due to less no. of coarse fibbers, have less area of surface of frictional contact, than the fine fibers yarn where area of frictional contact of fiber surface are more. For this reason yarn produced from fine fibers shows more strength than the coarse fiber yarn.
Strength & Extension: The tensile strength of fiber is its fundamental ability to resist Strain or rupture induced by tension. It is expressed as the force per unit X-sectional area. Tenacity of a yarn, however, is defined as the strength per unit yarn number, where the yarn number is expressed as a weight per unit length. Tenacity of fibers breaking loads Fiber Tex. The percentage of increased length With respect to original length is the extension at break. Strength & Extension of fiber is important due to.
Work of rupture: The bigger the work of rupture the greater the energy required to break.
Strength: Strong the fiber stronger the yarn & fabric.
Elastic Property: The elastic property of a material usually expressed as elastic modulus or the load required to stretch a sample a unit amount. The elastic limit is the greatest stress intensity to which a fiber or yarn can be subjected without the occurrence of a permanent set when the load producing the stress is removed. It has a considerable influence in the extensibility of materials made out of fibers, and also on the set or setting of fibrous materials. This is important when fibers are subject to repeated loading, as in tyre, and heating will affect their properties. Textile materials are somewhere between elastic & plastic. Yield point is the elastic limit point. Elastic fiber does not crease. Amount of moisture & heat present in the fiber governs the elastic or plastic nature. By applying heat elastic property can be modified.
Fiber Cross Section: Different fibers are of different x-sectional shape. Changes in x- sectional shape into round one, gives better bending rigidly, fiber cross-section also influences the bulk, softness, warmth, coldness of yarn & fabric. The common fiber cross-sectional shapes are:
Cotton – Ribbon Shape
Silk – Triangular.
Ravon – Star-shape
Polyester – Round/oval
Appearance: Fiber appearance such as color, luster, and cleanliness affects the quality & commercial valuation of fiber, some fibers are classified or graded on the basis of the color of the fiber e.g. cotton. Fiber cleanliness influences the price of fibers. Fiber luster influence the fabric luster. Some times for fiber identification fiber appearance is also considered.
Crimp: Crimp is the waviness of fiber. It is a calculate of the difference between the length of the none straighten fibers and that of a straighten fiber. Expressed as the percentage of the none stretched length. Crimp of the fiber helps in spinning yarns & to retain twist in the yarn. Crimp fiber produces soft handle & Worm material on the other hand straight fiber produces relatively harder handle & cool materials. .
Friction: Friction is the force which holds together the fibers in a spun yarn, and the interlacing threads in a fabric, if the friction is too low, the yarn strength will be low and dimensional stability of cloth will be reduced. Here high friction is an advantage, enabling a greater proportion of the strength of the individual fibers to be utilized. In many other places fiber friction is disadvantageous e.g. a yarn passes round a guide. In stretching of fabric high friction causes frequent end breakage. There are many other aspects which are influence by the frictional characteristics of fiber, e.g. the handle & wear resistance of fabrics, the behavior of fibers during drafting etc.