Fundamentals of Textile & Man made fiber

• Textile & Textile fiber• Man-made fiber & it’s classification • Definition of different types of man made fiber • Flow chart of synthetic process of man made fiber.. Textile, Textile F

Southeast University

Department Of Textile Engineering

I/A 251,252 Tejgaon Dhaka Bangladesh

Prepared by : Mazadul Hasan sheshir

Welcome

to our presentation

• Textile & Textile fiber

• Man-made fiber & it’s classification

• Definition of different types of man made fiber

• Flow chart of synthetic process of man made fiber

• Properties of man made fiber

• Influence of chemical structure on man made fiber

• Spinning process & it’s general principle

• Different types of spinning process with figure

• Viscose & it’s manufacturing process

• Note on cuprammonium rayon

• Lyocell & its process flowchart

• Notes on cotton count ,Denier, tex , millitex & their conversion

Textile, Textile Fiber & it’s classification

Textile : A textile is a flexible material consisting of a network of natural or artificial

fibers oftenreferred to as thread or yarn.

Textile Fiber: Textile fibers are defined as unit of matters characterized by flexibility,

fineness, and high ratio of length to thickness.

Classification of Textile Fibers:

• Naturally occurring fibers of vegetable origin.

• Naturally occurring fibers of animal origin.

• Regenerated man-made fibers which use some naturally occurring substance as the raw material.

• Synthetic man-made fibers which use synthetic organic compounds as the raw

material.

• Mineral fibers which are entirely inorganic.

The denier of a yarn is the wt in gms of a length of 9000m of that yarn.

• The coarseness of a yarn or a filament is usually gauged as denier.

• Denier is a unit of measure for the linear mass density of fibers.

• If 9000 meters of yarn weigh 100 grams - the yarn is said to be 100 denier.

• The term micro-denier is used to describe filaments that weigh less than one gram per 9,000 meter length.

• Filament Denier only relates to a single filament

• Total Denier relates to a yarn, an agglomeration of filaments.

Total Denier

• D.P.F =

Quantity of Uniform Filaments

(D.P.F is commonly known as Denier per Filament)

• If a yarn of 100 denier is composed of either 20 or 60 filaments, then the filament denier will be:

• For 20 filaments yarn, D.P.F =100/20 =5 denier -coarse filament

• For 60 filaments yarn, D.P.F =100/60 =1.7 denier -fine filament

Cotton Count, Tex & millitex

The yarn numbering system based on length and weight originally used for cotton yarns and now employed for most staple yarns spun on the cotton or short-staple, system

• It is based on a unit length of 840 yards, and the count of the yarn is equal

to the number of 840-yard skeins required to weigh 1 pound

• Under this system, the higher the number, the finer is the yarn

Tex is a unit of measure for the linear mass density of fibers

and is defined as the mass in grams per 1000 meters

The most commonly used unit is actually the decitex

abbreviated dtex, which is the mass in grams per 10,000

meters When measuring objects that consist of multiple fibers the term "filament tex" is sometimes used, referring

to the mass in grams per 10,000 meters of a single

filament

Conversion factor for 1s cotton counts

• 840 yds of cotton weighs =1 lb

(equivalent denier or conversion factor)

Therefore, for 25s, Denier (D) = 5315 / 25, that is, D = 5315 / C

• 50s cotton count = 5315/50 = 106.3 denier

• 2/50s cotton count = 5315/25 = 212.6 denier

• 106.3 denier = 5315/106.3 = 50s cotton count

Man-made fiber & it’s classification

Man-made Fiber : A class name for various fibers (including filaments)

synthetically produced from fiber-forming substances which usually refer

to all chemically produced fibers to distinguish them from truly natural fibers such as cotton, wool, silk, flax, etc

Classification:

Man made fiber can be classified into three classes:

a Those made from natural polymers

b Those made from synthetic polymers

c Those made from inorganic materials

Classification flowchart of man made fiber

Organic

Man Made Fibres

Carbon Ceramic Glass Metal

Flow chart of synthetic process of man-made fiber:

Synthetic fiber has its beginning with chemistry

A media is developed & is filtered under pressure

It is then extruded into continuous filamentsThe filaments are allowed to solidify

Then they are stretched

A finishing solution is then appliedThen the bundle of filaments is crimpedCutting the bundle into staple length

Different types of man made fiber.

Regenerated Fiber: The man-made fibres, derived from naturally occurring

polymers are known as regenerated fibres For instance rayon and acetate are made of the same cellulose polymers that make up cotton In the case of rayon and acetate, the cellulose is acquired in an altered state usually from wood-

produced from these polymers include nylon, polyesters, acrylics, the

polyurethanes, etc

Inorganic Fiber: The man made fiber ,derived from inorganic substance is

called inorganic fiber.Glass , Carbon, Ceramic & Metal are the example of inorganic fiber

Basic Characteristics: A synthetic polymer must have to have suitable

characteristics with respect to several physical and chemical properties.These are:

a A high softening point

b Adequate tensile strength

c Soluability or melting ability for spinning

d A high modulus or stiffness

In addition to the primary requirements, many other

properties of the material are important

Chemical Physical Biological Fabric

Thermal

-melting point -softening point -glass transition temperature -decomposition temperature

Electrical

-surface resistivity

Toxicological Dermatological Resistance to

-bacteria -molds -insects

Appearance

-drape -hand -lustre

Comfort

-warmth -water sorption -moisture retention -wicking

Stability

-shape -shrinkage -felting -pilling -crease resistance -crease retention

Influence of chemical structure on

properties

Olefins (alkenes), a family of hydrocarbon compounds—which are produced from the refining of

petroleum and natural gas —contains one double bond between two carbon atoms The

general chemical formula can be represented as CH 2 =CHR, with R representing any of

several possible atoms or groups of atoms

As the repeating unit of a polymer,

the compound has the following chemical structure:

Polypropylene is a material of moderately high melting

temperature (176 °C) that can be melt-spun into fibres

useful for several types of clothing, upholstery, carpets, and nonwoven fabrics When R is hydrogen (H), the polymer is polyethylene, a relatively low-melting material (137 °C) that finds use as a fibre in industrial applications—e.g., nonwoven fabrics—but not in most

Different Types of Spinning

There are typically three types of spinning for polymers:

Melt, Dry and Wet

▪ Melt spinning is used for polymers that can be melted easily

▪ Dry spinning involves dissolving the polymer into a solution that can be evaporated

▪ Wet spinning is used when the solvent cannot be

means

Melt spinning

Melt spinning is the preferred method of manufacture for polymeric fibers The

polymer is melted and pumped through a spinneret (die) with numerous holes (one to thousands) The molten fibers are cooled, solidified, and collected on a take-up wheel Stretching of the fibers in both the molten and solid states

provides for orientation of the polymer chains along the fiber axis Polymers such as poly(ethylene terephthalate) and nylon 6,6 are melt spun in high

volume.

Dry Spinning

Dry Spinning: In dry spinning the fibre-forming substance is

dissolved in a

solvent before the solution is extruded As the jets of solution

emerge from the

spinneret, a stream of hot air causes the solvent to evaporate from the spinning

solution, leaving solid filaments Acetate is dry spun by extruding acetone

solutions of cellulose acetate into hot air.

Wet Spinning

Wet Spinning: In wet spinning the solution of fibre-forming material is extruded into a

coagulating bath that causes the jets to harden as a result of chemical or physical

change.Viscose, for example, is wet spun The solution of cellulose xanthate is

extruded into an aqueous solution of acids and salts, in which the cellulose is

regenerated to form solid filaments

Comparative features of melt, dry and wet spinning

explosion)

Toxic

Manufacture of viscose rayon

Viscose rayon is a regenerated cellulose fibre Because it is produced from naturally occurring polymers.The raw materials for viscose rayon may be cotton linters, the short fibres adhering to the cotton seed, or wood pulp derived from northern spruce, western hemlock, eucalyptus, or southern slash pine The pulps of these soft woods, containing about 94 percent cellulose, are especially suited to fibre manufacture Wood contains other substances like lignin, besides cellulose So it is purified, treated with caustic soda, which converts it into alkali cellulose, then treated with carbon disulphide, which converts it into sodium cellulose xanthate and then dissolved in dilute solution of caustic soda The solution is then “ripened” and then spun into an acid coagulating bath, which precipitates the cellulose in the form of a viscose

filament

Manufacture Process Flow Chart

Preparation of the wood pulpConditioning of Wood PulpSteeping (formation of soda cellulose)

Shredding (cutting)

AgeingChurning (Xanthation or Sulphidising)

Mixing (dissolving)

RipeningSpinningWind up/Cutting