Textile fibers - Definition of Fiber and Textile Fibers

CHAPTER ONE INTRODUCTION TO TEXTILE FIBERS Definition of Fiber and Textile fibers  Fiber:  It is defined as one of the delicate, hair portions of the tissues of a plant or animal or other substances that are very small in diameter in relation to there length.  A fiber is a material which is several hundred times as long as its thick.  Fibres have been defined by the Textile Institute as units of matter characterized by :  flexibility,  fineness  high ratio of length to thickness. Cont…  Other characteristics might be added, if the fibre is to be of any use for general textile purposes, a sufficiently high temperature stability and a certain minimum strength and moderate extensibility.  The characteristic dimensions of fibres are the basis of their use and need to be stressed:  individual fibres (or elements of a continuous filament) weigh only a few micrograms  their length/width ratio is at least 1000:1  It is the basic structural element of textile products.  It is a smallest textile component which is microscopic hair like substance that may be manmade or natural. Textile Fiber:  Textile fiber has some characteristics which differ between fiber to Textile fiber.  Textile fiber can be spun into a yarn or made into a fabric by various methods including weaving, knitting, braiding, felting, and twisting.  The essential requirements for fibers to be spun into yarn include a length of at least 5 millimeters, flexibility, cohesiveness, and sufficient strength.  Other important properties include elasticity, fineness, uniformity, durability, and luster.  Banana fiber is one kind of fiber but it is not a textile fiber. Because it can not fill up the above properties. So we can say that all fiber are not textile fiber. Cont…  ordinary textile fibres must be, at least partly, elastic up to breaking extensions between 5 and 50%.  This is an unusual intermediate range of extensibility, since glasses and crystalline solids are less extensible, whereas rubbers are much more extensible.  all textile fibers are partially oriented, linear polymers.  A remarkable fact is that almost all the general textile fibre market is met by six polymer types:  the natural polymers,  cellulose and proteins,  the synthetic (manufactured) polymers, polyamide, polyester, polyolefin and vinyl (including acrylic). Essential properties Textile Fibers  Basic Textile Fiber Properties  There are several primary properties necessary for a polymeric material to make an adequate fiber.  Certain other fiber properties increase its value and desirability in its intended end-use but are not necessary properties essential to make a fiber. Such secondary properties include :  moisture absorption characteristics,  fiber resiliency, abrasion resistance,  density,  luster,  chemical resistance,  thermal characteristics,  flammability. CONT  Some Primary Properties of Textile Fibers are:  Fiber length to width ratio,  Fiber uniformity,  Fiber strength and flexibility,  Fiber extensibility and elasticity,  Fiber cohesiveness. CONT.  Length to Width Ratio: Fibrous material must possess adequate staple or fiber length and the length must be considerably higher (1000 times) then the width of the fiber. Length to Width Ratio of Some Typical Fiber as follows: • But to be a fiber the staple length must not be less than ½ inch. According to the length, the fibers may be classified into the following two categories: Staple Fiber, Filament Fiber Fiber Length to Width Ratio Cotton 1400 Wool 8000 Flax 170 Silk 330000 Cont… Strength:  Strength of any material is determined by the breaking strength (that is tenacity strength) which express as force per unit cross-sectional area.  With this term (strength / tensile strength) we may describe the ability of a bundle of fiber of yarn to resist breakage under tension / load.  In case of describing the strength of individual fiber the term tenacity is usually used.  Tenacity :force per unit linear density That is, tenacity = breaking load/ mass per unit length Tenacity express as grams per tex(gtex) or grams per denier(gd). Tenacity of Some Common Fiber: Fiber Grams Per Denier Raw cotton 3.0 - 4.9 Jute 3.0 - 5.8 Flax 2.6 - 7.7 Ramie 5.5 Silk 2.4 - 5.1 Wool 1.1 - 1.7 Hemp 5.8 - 6.8 [...]... is one of the essential property of textile fiber  The fibers should be sufficient by poliable, then only it can be wrapped around another fiber during spinning  Many substance in nature resemble fibrous forms but they are note pratical fibers as they are stiff and brittle Cohesiveness:  It may also be termed as spinning quality of fiber  It is the property of an individual fiber by virtue of which... elastic recovery of a fiber is determined by several aspects like what type of load is applied and how many times it is held in the stretched position CLASSIFICATION OF FIBRES The history of Traces of natural fibers have been located to ancient civilizations all over the globe For many thousand years, the usage of fiber was limited by natural fibers such as flax, cotton, silk, wool and plant fibres... applications Fibers can be divided into natural fibres and man-made or chemical fibres Flax is considered to be the oldest and the most used natural fibre since ancient times Classification of Fibres  Natural Fibers  Vegetable Fibres  Animal Fibres  Mineral fibers Man Made fibers Regenerated fibres Synthetic fibres Inorganic fibres Inorganic fibres Cont…  Classification of fibers can be... obtained from varieties of rocks properties It is fibrous form of silicate of magnesium and calcium containing iron and aluminum and other minerals It is acid proof, flame proof and rust proof Its particles are carcinogenic and hence its use is restricted MAN MADE Regenerated Fibres Cellulosic– Cotton linters and wood pulp Viscose rayon, Cupra-ammonium, Cellulose Acetate (secondary and triacetate),... which the fibers are hold on to one another when the fibers are spun into yarns Cont… Uniformity:  It may describe the similarities in length of fiber which are spun into yarn  To make a good quality yarn, it is important that the fibers must be similar in length and width in spinning quality and in flexibility  There is no problem in producing uniform manmade fibers but for natural fiber uniformity... remove the fiber from the stem, the hemp naturally maybe creamy white, brown, gray, black or green Properties it is yellowish brown fibre Hemp fibers can be 3 to 15 feet long, running the length of the plant Characteristics of hemp fibre are its superior strength and durability, resistance to ultraviolet light and mold, comfort and good absorbency ANIMAL FIBRES Animal fibers are natural fibers that... stem of a certain plant Properties The bast fibres have often higher tensile strength than other kinds, and ropes, yarn, paper, composites and burlap A special property of bast fibers are that the fiber at that point represents a weak point They are obtained by the process called retting JUTE FIBRE  Jute is one of the cheapest natural fibres and is second only to cotton in amount produced and variety... composed primarily of the plant cellulose and lignin Properties Jute is a long, soft, shiny vegetable fibre that can be spun into coarse, strong It is a lingo -cellulosic fibre that is partially a textile fibre and partially wood The plant grows up to a height of 2.5m and its fibre length is about 2m it is generally used in geo textiles it has a good resistance to microorganisms and insects it... wood pulp with acetic acid and acetic anhydride in the presence of sulfuric acid Acetate Fiber Characteristics  Luxurious feel and appearance  Wide range of colors and lusters  Excellent drapability and softness  Relatively fast drying  Shrink, moth and mildew resistant  Special dyes have been developed for acetate since it does not accept dyes ordinarily used for cotton and rayon ... Azlon fibre from corn and Natural man made fibre (A) Cellulosic fibres Cellulose is one of many polymers found in nature Wood, paper, and cotton all contain cellulose Cellulose is an excellent fiber Cellulose is made of repeat units of the monomer glucose  The three types of regenerated cellulosic fibres are rayon, acetate and triacetate which are derived from the cell walls of short cotton fibres . CHAPTER ONE INTRODUCTION TO TEXTILE FIBERS Definition of Fiber and Textile fibers  Fiber:  It is defined as one of the delicate, hair portions of the tissues of a plant or animal or other. Tenacity of Some Common Fiber: Fiber Grams Per Denier Raw cotton 3.0 - 4.9 Jute 3.0 - 5.8 Flax 2.6 - 7.7 Ramie 5.5 Silk 2.4 - 5.1 Wool 1.1 - 1.7 Hemp 5.8 - 6.8 Cont… Flexibility:  It is one of the. pratical fibers as they are stiff and brittle. Cohesiveness:  It may also be termed as spinning quality of fiber.  It is the property of an individual fiber by virtue of which the fibers