For thousands of years, cotton has been used to make lightweight cloth in tropical areas. Some people claim that the ancient Egyptians used cotton for 14,000 years ago. Proof was found that Mexican people used cotton for 7,000 years ago (cotton cloth and fragments were found in caves). Around 300 BC Alexander the great brought cotton into Europe. When it first came there it was so expensive that only rich people could afford buying it. In the 17th century American colonies began growing cotton. Slaves were used up until the abolition of slavery. The main use of the cotton in that time was for clothing.
In 2002, cotton growing took up 330,000 Km² of farmland. This made 21 million tons of raw cotton. The whole amount added up to a worth of 20 billion US dollars. The industry of cotton relies heavily on chemicals such as fertilisers and insecticides. As the new time has grown farmers have found ways to grow cotton non-chemically and that is a very good thing. Most cotton is harvested mechanically, either by a cotton picker, a machine that removes the cotton from the boll without damaging the cotton plant, or by a cotton stripper which strips the entire boll off the plant. The case of cotton harvesting and processing has been improved by the development of the cotton module builder, a machine that compresses harvested cotton into a large block, which is then covered with a tarp and temporarily stored at the edge of the field.
Preparation of Cotton Fabrics Before processing cotton, there are three steps to go through 1. Ginning – separates the cotton fibers from the seedpods 2. Spinning – Several fibers are twisted together to bind them into a strong, long yarn. 3. Weaving – To turn the fibres into cloth by interlacing them.
Cotton Processing After weaving, cotton passes through many processing stages. Many factories use these stages: 1. Singeing – Burning the loose fibres sticking out of the cloth 2. Desizing – Desizing is the process of removing the size material from the yarns in woven fabrics. 3. Scouring – cleaning the yarn off. 4. Bleaching – Apply chemicals to the yarn in order to make it look white. 5. Mercerizing – making the cotton stronger. 6. Dyeing – Changing the color. 7. Finishing – making the last small details.
Uses of Cotton Cotton is used for many more things than clothes, for example many countries use cotton for their money because it does not get damaged in water. Cotton is also used in fishnets, coffee filters, tents and bookbinding.
You can machine wash cotton on a quite high temperature, from 40-90 degrees. 90 C º for bed linen. Tumble dry it or you can just hang it up on a hanger to dry. When ironing, iron it on a high temperature, if the care label doesn’t suggests anything else. Also iron it when the piece of fabric is damp.
The advantages of cotton are: cool, strong and long lasting. The disadvantages are: Burns very easily, gets wrinkled and shrinks.
Weaving is the most basic process in which two different sets of yarns or threads are interlaced with each other to form a fabric or cloth. One of these sets is called warp which is the lengthwise yarn running from the back to the front of the loom. The other set of crosswise yarns are the filling which are called the weft or the woof.
Type of fabric weave
The fabric weave is the pattern for manufacturing a fabric. The yarns are used in different ways to produce various effects or weaves. These weaves can be plain and simple as well as artistic and decorative.
Plain weave is the most simple and common type of construction which is inexpensive to produce, durable, flat having tight surface on which printing and other finishes can be easily applied. The examples of plain weave fabrics are crepe, taffeta, organdy, cotton calicos, cheesecloth, gingham, percale, voile and muslin.
Satin weave, although more complicated, is a flexible type of weave than the plain weave. It is called 'satin' when filament fibers such as silk or nylon are used and is called 'sateen' when short-staple yarns like cotton is used to make it. The satin weave is lustrous with a smooth surface and it drapes in an excellent manner. The examples of satin weave fabrics are bocade, brocatelle, crepe-satin, satin, peau de soie, velvet satin etc.
Twill weave is somewhat similar to plain weave. Twill weave is durable, heavier, wrinkle and soil resistant, and is more flexible than plain weave. The examples of twill weave fabrics are covert cloth, drill, jean, jersey, tussah, velvet, worsted cheviot etc.
Basket weave is a variation of plain weave in which the fabrics have a loose construction and a flat look. It is more flexible and stronger but less stable than a plain weave. This weave is used in composites industry, outerwear, monk's cloth and drapery fabrics etc.
Jacquard weave is for creating complex patterns on fabrics and is woven on jacquard loom. The fabrics made through this weave have floats, luster, and are more stable and stretchy than the basic weaves. Some of its examples are matelasse, satin Faconne etc. It is used for upholstery and drapery.
Rib weave is a basic weave which produces ribs on the fabric. Resulting fabric is abrasion and tear resistant examples of which are broadcloth, cord fabric, faille, poplin, taffeta etc.
Dobby, a decorative weave results in small designs or geometric figures all over the woven fabric. It is done through dobby machines. This weave uses various yarns from very fine to coarse and fluffy yarns to produce a variety of fabrics. The standard dobby weave fabrics are flat and comparatively fine. Some examples are moss crepe, matelasse etc. Heavy dobby fabrics are used for home furnishings and for heavy apparel.
Leno weave fabric is transparently thin, durable, strong and permits passage of both light and air through it. Examples of fabrics with leno weave are gauze, net, tulle etc. The leno weave fabrics are used for light-weight membrane, laminating fabrics, making medium weight blankets etc.
Oxford weave fabrics are made with modified plain weave or basket weave and are generally used for apparels, particularly cotton shirting materials. The fabric is fine, soft and lightweight.
Cut pile is a carpet fabric in which the surface of the carpet is made of cut ends of pile yarn. It is durable depending upon the kind of fiber used, density of the tufts and the number of twists in the yarn.
Examples of cut pile are cisele velvet, velour , saxony etc.
Uncut pile, also called loop pile or rounded loops, produces fabric without cutting the ends of yarns as opposed to cut pile. The resulting fabrics are very strong with which very strong carpets are made. They are also used for making towels. Examples are terry cloth, terry velour, moquette, etc.
Double knit is a circular knit fabric having loops on both sides. It is made on circular knitting machines. The constructed fabric is very heavy. The fabrics such as cotton, wool, silk, rayon and synthetics are used for double knit and are made into pants, skirts, tunics, jackets, scarfs, hats, bandages etc.
Chenile fabric is usually a soft wool, silk, cotton, or rayon yarn with protruding pile having fur-like texture which resembles velvet. It is generally used for making sweaters, outerwear, upholstery, curtains, rugs, throws and blankets etc.
Textiles are important for everyone. It is used for covering body, for warmth or coolness, personality enhancement and sometimes to display one's status in the society. From the wholesale textile manufacturer and merchant to the retailer and the end- user, the customer, everyone consumes textile. Not only those who are in this direct trade are related to this product but there are certain industries which are indirectly associated with textile. Automobile industry is a good example of this type of industry which uses textile in various forms. Others who use textile in one or the other form may include designers, interior decorators, craftspersons, advertisers using hoardings and banners, painters etc.
Weaving- What is it Weaving is a major process of making fabric or cloth . In it, two distinct sets of yarns called the warp and the filling or weft are interlaced with each other to form a fabric. Yarn is a long continuous length of interlocked fibers. The lengthwise yarns which run from the back to the front of the loom are called the warp. The crosswise yarns are the filling or weft. A loom is a device for holding the warp threads in place while the filling threads are woven through them. Yarns made from natural fibers like cotton, silk, and wool and synthetic fibers such as nylon and Orlon are commonly used for weaving textile. But other fibers can also be used for weaving. Yarn intended for the warp goes through operations such as spooling, warping and slashing to prepare them to withstand the strain of the weaving process.
Weaving operations Four major operations are involved in weaving- Shedding, Picking, Beating up (Battening) and Taking up and letting off.
Shedding Each alternate warp yarn is raised to insert the filling yarn into the warp to form a shed.
Picking As the warp is raised, the filling yarn is inserted through the shed by a carrier device. Different types of looms are used for carrying the filling yarn through the shed- Shuttle loom, shuttle less looms, circular looms etc.
Beating up (Battening) With each picking operation, the reed pushes or beats each filling yarn against the portion of the fabric that has already been formed. Reed is a comb like structure attached to the looms. It gives the fabric a firm, compact construction.
Taking up and letting off With each shedding,Picking, Battening operation, the new fabric must be wound on the cloth beam which is called 'taking up'. At the same time, the warp yarns must be released from the warp beam which is called l 'letting off'.
As the shuttle moves back and forth across the width of the shed, a self edge is woven which is called selvage or selvedge. The selvage prevents the fabric from muddling. It is usually more compact and strong than the rest of the fabric. There are different kinds of selvages depending upon the expected use of the fabric- Plain Selvages, Tape Selvages, Split Selvages, Fused Selvages, Leno Selvages and Tucked Selvages.
Knitting After weaving, the most prevalent method of fabric construction is knitting. Its popularity has grown tremendously over the recent years . Today, knitting is a very big industry which has two main divisions.
One division manufactures knitted goods for apparel production, sewing centers, consumers and others. The other division manufactures finished apparel such as hosiery, sweaters and underwear.
The knitted fabric has the advantage of stretchability which provides fit and comfort. It also gives warmth. At the same time, they are porous and provide breathing comfort. It is light in weight and wrinkle- resistant. However, certain specialized techniques like Pak- nit or Permasized have to be used so that it may not shrink too much. Also, care should be taken so that not a single loop breaks. If even one loop breaks, a hole is made and it starts running. This disadvantage can be eliminated by variation in the stitch that protects the fabric from raveling.
The kind and quality of the needle also affect the quality of the knitted fabric. Different kinds of needles are used in knitting latch needle, spring- beard needle, compound needle etc.
Weft and warp knitting There are two major varieties of knitting: weft knitting and warp knitting. In weft knitting, one continuous yarn forms courses across the fabric. In warp knitting, a series of yarns form wales in the lengthwise direction of the fabric.
The knitting machine also called knitting frame, knitting loom, or hand knitting machine, is used to manufacture knit fabrics. These fabrics are produced on a fixed bed of hooked needles. The Knitting machines can be hand driven or motor powered.
The machines come in domestic and industrial models, with either flat or circular beds that produce rectangular or tubular fabrics. The fabric produced by a knitting machine has a more fine texture than hand-knitted fabric.
Wool has been available since the day sheep set their feet on earth, but it has been used since the shear was invented. The properties of the different types of wools aren’t so different. They are only different because the different wools come from different animals. Then the shape of the wool is depending on the race of the animal, the climate in its habitat and what it eats. All these things decide how the different kinds of wool are like.
The 4 biggest producers of wool are:
1. Australia, with 29, 1% of the market with unwashed wool and 31, 6% of the degreased wool market.
2. New Zealand, with 10, 4% of the market with unwashed wool and 13, 1% of the degreased wool market.
3. China with 10, 3% of the unwashed wool market and 9, 0% of the degreased wool market.
4. Russia, with 3, 9% of the market with unwashed wool and 4, 0% of the degreased wool market.
The process of wool starts when the sheep gets cut. This is mostly done with a machine nowadays. Before there were machines the sheep were cut with a shear like on the picture →
When all the wool is collected you have to wash it for 2-3 days. While you are washing it you have to dry it on a flat surface and NOT hang it up, that will make it stretch.
When you wash wool you have to activate a special “wool function” that most modern washing machines have. When ironing wool the iron must not touch the surface of the wool because it will ruin the fabric. To not ruin it you have to hold the iron around 2 cm above the surface.
Uses of Wool
Some uses of wool are sweaters, blankets, coats, suits, shirts, pillows and hats.
The most common one of these is the sweater, which is very popular here in Sweden.
Advantages of wool are: Absorbent, elastic, comfortable, easy to get, washable and it is a good insulator. Disadvantages are: it is expensive, it can be itchy, and it is the weakest of these ten fabrics and is sensitive to alkaline.
Silk is, has been and will always be a luxury product. It is very soft and very comfortable to wear. Silk was originated in china where there where bugs that actually created it. To be more accurate, the bugs are moths that spin themselves into a cocoon made up of silk to protect them. When the cocoon was finished the Chinese women collected all the cocoons and boiled them in water so the moths died. When all the moths were dead they separated the silk from the moths and made it into strings.
Silk is white with a touch of grey that you never see because it has already been dyed into another colour.
There are two types of silk, natural and synthetic. Synthetic silk is made from lyocell which is a cellulose fibre. The difference between the both is hard to see and feel.
If you want to wash silk it is very important that you use non-alkaline soap and water. To dry the silk take a towel and roll it in, then take it out and let it lay on a flat surface.
One big disadvantage with silk is that it gets destroyed in high temperatures, so you can’t
Iron it in high temperatures.
Silk is used for many things like clothing, mats, and towels and so on.
Silk Manufacturing Process
Silk is a natural protein fiber produced by certain caterpillars in order to encase themselves in the form of cocoons. The making of silk is different from that of other natural fibers. There are many steps involved in silk manufacturing
Kinds of Silk Yarns
Thrown Singles: Three to eight silk filaments are twisted together in only one direction to make 'Singles'.
Tram: A slight twist is given to two to four untwisted singles. Trams are used exclusively as filling yarns.
Crepe: Individual raw silk filaments are twisted together, one in S direction and the other in opposite Z direction. They are then twisted around each other in S direction.
Organzine: Two or more singles having twist in Z direction are combined by twisting them around each other in the opposite S direction. Organzine is mainly used for warp yarns.
Finishing of Silk Fabrics
Many finishing processes are applied to different silk fabrics in order to improve their appearance, durability and feel. Calendering and Cireing is done to enhance luster, singeing is done to make them smooth, and steaming is done for raising pile weaves. Pressing and lustering removes wrinkles from the finished fabric. It is done with heated rollers and then soaking in dilute acid to bring luster.
One finish that is unique to silk fabric is 'Weighting'. The weight of silk is lost during the process of demugging. The manufacturer purchases silk by weight and to make up his loss, he does weighting of silk fabric with metallic substances such as stannic chloride, sodium phosphate, iron salt, logwood etc. Weighting is done during the dyeing process. Weighted silk is less compactly woven when compared to the unweighted silk and lesser silk is used in the fabric construction. Apart from lowering the cost of silk, weighting gives it crispness, luster and a firm feel.
Fiber Spinning
Spinning is the twisting together of fibers to form yarn (or thread, rope, or cable). Earlier fiber was spun by hand using simple tools like spindle and distaff. Later the use of spinning wheel gained importance. Industrial spinning started in the 18th century with the beginning of the Industrial Revolution. Hand-spinning remains a popular handicraft.
Industrial spinning
Fibers can not be used to make clothes in their raw form. For this purpose, they must be converted into yarns. The process used for yarn formation is spinning. Spinning by hand was a slow and laborious process. Thus, Many implements and methods were invented for making it faster and simple. Eventually, the techniques were refined and industrial spinning started manufacturing yarn in various ways. The methods selected depend upon the factors such as the manufacturer's preference of equipment, the economic implications, the fibers to be used and the desired properties of yarn to be produced. Ring method is the oldest and the most used technique. Open- end spinning is another important method. The basic manufacturing process of spinning includes carding, combing, drafting, twisting and winding. As the fibers pass through these processes, they are successively formed into lap, sliver, roving and finally yarn. A brief description of the journey from fibers to yarns will help in understanding industrial spinning in a better way.
The raw fiber arrives at a spinning mill as compressed mass which goes through the processes of blending, opening and cleaning. Blending is done to obtain uniformity of fiber quality. Opening is done to loosen the hard lumps of fiber and disentangle them. Cleaning is required to remove the trash such as dirt, leaves, burrs and any remaining seeds. Carding is the initial straightening process which puts the fiber into a parallel lengthwise alignment. This makes the tangled mass of fiber ready to produce yarn. Now the fiber is called 'Lap' . The lap is treated for removing the remaining trash, disentangling and molding it into a round rope like mass called 'Sliver'. The sliver is then straighten again which is called Combing. In it, fine-toothed combs continue straightening the fibers until they are arranged in such a parallel manner that the short fibers are completely separated from the longer fibers. This procedure is not required for man made staple fiber because they are cut into predetermined uniform lengths. This process forms a 'comb sliver' made of the longest fibers. The combing process is identified with better quality because long staple yarn produces stronger, smoother and more serviceable fabrics.
Drawing pulls the staple lengthwise over each other. As a result longer and thinner slivers are produced. After several stages of drawing out, the sliver is passed to the spindles where it is given its first twist and is then wound on bobbins. 'Roving' is the final product of the several drawing-out operations. It is the preparatory stage for the final insertion of twist. Till now, enough twist is given for holding the fibers together but it has no tensile strength. It can break apart easily with a slight pull. The roving, on bobbins, is placed in the spinning frame, where it passes through several sets of rollers running at high speed and finally the 'Yarn' is produced of the sizes desired.
Spinning Machines Traditional v/s Modern Techniques
Hand spinning was replaced by powered spinning machines which was very fast. Initially it was done by water or steam power and then by electricity. The spinning jenny, a multi-spool spinning wheel significantly reduced the amount of work required to produce yarn. A single worker was now able to work eight or more spools at a time.
Then came the spinning frame which produced a stronger thread than the spinning jenny. As it was too large to be operated by hand, a spinning frame powered by a waterwheel was invented. It was then called the water frame. The elements of the spinning jenny and water frame were combined to create the spinning mule.
Then came the spinning frame which produced a stronger thread than the spinning jenny. As it was too large to be operated by hand, a spinning frame powered by a waterwheel was invented. It was then called the water frame. The elements of the spinning jenny and water frame were combined to create the spinning mule.
Nylon is a synthetic polymer, a plastic, invented on February 28, 1935 by Wallace Carothers at DuPont of Wilmington, Delaware, USA. On the 28th of February 1938 the first nylon product was announced, a nylon bristle toothbrush made up of nylon yarn. In 1940, women’s’ stockings were announced. Nylon fibres are now used to make many synthetic fabrics, and solid nylon is used as an engineering material.
Nylon is made through this process: Polymer molecules are pumped into an airshaft where they are stretched and solidified. After that the fibres are put into piles and then you melt them again and take them to the airshaft where they are solidified and stretched again. This process is repeated several times to make the nylon get stronger.
Some of the uses for nylon are: Clothes, car accessories, nets, threads etc. These things need to be like nylon is, elastic and quite strong.
To iron nylon, you need a really hot iron if the clothing doesn’t say anything else. When you wash it you have to have a fairly low temperature.
The advantages are: Strong fabric, elastic and long lasting. The disadvantages are: very good conductor of electricity, doesn’t absorb water well and is sensitive against chemicals.
Linen is made from a plant in the lineum family called flax. You take the stalks that hold the fibre and work so it becomes linen with help from many different chemicals. The last part is when you pack the linen up. The best way is to pack it with water which gives you the best yarn.
Linen has been used since 7,000 years ago. It was in the Ancient Egypt that this was used. The flax plant was one of the major plants that they planted. While today, China is the biggest producer of linen.
Linen is commonly used in kitchens and bedrooms, in for example cloth, canvases, sails, tents, and paper. Linen is also used for decorations. Linen is also a very strong fabric; it was used for shields and gambesons during the medieval time.
Have a degree of about 50 degrees when you machine wash linen, you should also be aware of that if you have washing powder, this will bleach the linen. Be sure not to have other clothes in the washing machine at the same time as you wash the linen, this will make the linen look ugly. When you iron it the linen must still be damp and the iron on a high temperature.
The advantages with linen are: It is very strong, it is nice to touch and it is beautiful. The disadvantages are: It is easily creased and hard to iron.
In this age of specialty based environment, everything connected to highly technical man needs to be special. Fabrics are no exception. Many types of specialty fabrics go to serve the cause of consumer, industrial, medical, and military applications. Coated fabric is one such specialty fabric which has been there for a long time and is being refined with the time.
Any woven or a non-woven fabric, when coated with something like plastic resin, rubber, elastomers, fluoropolymer such as PTFE or Teflon, can be called a coated fabric. As common a thing as canvas- wax coated cotton fabrics - is in fact a coated fabric. We may realize or not, coated fabrics are everywhere nowadays- from projection screens to window shade fabrics, from artist’s canvas to custom laminated fabric, from ground sheets to truck tarpaulins-all of them are coated fabrics.
Materials Used for Coating Fabrics
There are many coating formulations that are used for coating a fabric to make it suitable for a specific purpose.
·PVC (Polyvinyl Chloride)- PVC bags, rubber bath mat are made of them
·PE and other Poly olefins,
·PU (Polyurethane), such as PU coated leather
·Acrylics
·Rubber (natural or synthetic)
·Waxes
Coating is done to give specialized characteristics to a fabric such as to make them water repellent fabrics. A wide range of properties like water resistance, fire retardance, UV resistance, flexibility, surface gloss, surface texture, etc. can be given to a coated fabric through proper application of specific chemical and additive mix and compounds on the fabric substrate.
Coated fabrics are mainly used for making protective clothing
PVC coated fabrics: The PVC (Polyvinyl chloride) or polymer-coated fabrics are mainly used to make waterproof garments such as PVC rainwear. They are also used for making chemical protective clothing as well as industrial clothing that is oil and grease resistant.
Teflon coated fabrics: These coated fabrics are very strong and are used to make gaskets and seals in the automotive industry as well as conveyor belts for use in various industries.
Rubber coated fabric: They are used to make water resistant items such as bags and luggage bags. It is also used for heat curtains.
Vinyl coated fabrics: They are used to make water and mildew proof fabrics required for outdoor applications, such as for tents and tarpaulins.
TPO coated fabrics: Thermoplastic Polyolefin (TPO) is usually coated on polypropylene fabric (PP). These fabrics are used to make ground sheets, field covers, roofing membranes, sporting tents, light weight sport field covers, agriculture coverings, truck tarpaulins etc.
During the 1950’s, a fabric called acrylic was created by a company called DuPont in America. It was made of 85% of a synthetic fibre called acrylonitrile which was made up of small other chemicals. When it was exposed to light the acrylic turned yellow or brown. They had to make some small changes before they could manufacture it around America.
Today Acrylic is used a lot in the textile industry and is created in very big volumes; you can find it in many different variations like apparel including sweaters, fleece fabrics, and socks and in home furnishings such as furniture, carpet, blankets, and upholstery fabrics.
The acrylic fibres are very light and have a low absorbance of moisture. They keep the shape, they don’t get wrinkled so much and they don’t shrink.
When washing acrylic you should have around 40 Cº otherwise you can damage the fabric. But it handles acids, weak alkalis and organic materials. When you iron it you have to have a medium temperature.
Advantages are: handles many things, dries quickly, light, and handles chemicals well. Disadvantages are: burns easily, hard to pack it, bad heat resistance.
Nature of Life Trading is an importer and wholesaler of premium and exquisite fabrics. Based in Kuala Lumpur, Malaysia, we have been providing the apparel industry, fashion designers and fabric retailers with a large variety of fabrics. In order to achieve the best value and quality control, we import our fabrics from leading manufacturers around the world. We assure you of the most dependable customer service and a diverse styles of fabric. Our strength lies in the close collaboration we have with our clien Please t. This allows us to understand their needs and cater to their ever changing requirements based on the latest fashion trends in an efficient and effective manner. As we specialize in sourcing a huge variety of fabrics, our customers often seek our views and insights on the suitability and characteristics of fabrics. As such, we are always delighted to hear from you. Please do not hesitate to get in touch with us at enquiries.nature@gmail.com
The synthetic fabric polyester was created during the 50’s. It was invented in 1941 by John Rex Whinfield and James Tennant Dickson and was patented as polyethylene terephthalate. It was manufactured by the Du Pont de Nemours & Co.
There are two ways of making polyester, one way is: You react dimethyl terephthalate with ethylene glycol so you get bis-(2-hydroxyethyl) terephthalate and methanol. You have to turn the heat up to get rid of the methanol which will disappear at around 210 Cº.
Some uses of polyester are: Carpets, curtains, draperies, sheets and pillow cases.
Almost all polyester can be machine washed and machine dried. A fabric softener is needed for the rinsing part. To iron it, have medium iron warmth.
The advantages of Polyester are: strong, resistant to stretching and shrinking, resistant to most chemicals, quick drying, wrinkle resistant and easily washed fabric. Disadvantages are: burns easily, stains aren’t easy to take away if you machine dry it on a low temperature, can be sticky.
Types of Polyester
The polyester fibers are generally available in two varieties- PET (polyethylene terephthalate) and PCDT (poly-1, 4-cyclohexylene-dimethylene terephthalate). PET is the most common production. It is stronger than PCDT, while PCDT has more elasticity and resilience. PET can be used alone or blended with other fabrics for making wrinkle free and stain resistant clothing that can retain its shape. PCDT is more suitable for heavier applications, such as draperies and furniture coverings. Modifications can be introduced in each of these varieties for obtaining specific properties.
PET Polyester
For manufacturing PET Polyester, the main raw material is ethylene derived from petroleum. It is oxidized to produce a glycol monomer dihydric alcohol which is further combined with another monomer, terephthalic acid at a high temperature in a vacuum. Polymerization, the chemical process that produces the finished polyester, is done with the help of catalysts. The colorless molten polyester then flows from a slot in a vessel on to a casting wheel and takes shape of a ribbon as it cools to hardness. The polymer thus produced is then cut into very small chips, dried to remove all moisture and blended to make it uniform for getting it ready for spinning into yarn.
PCDT Polyester
This variation of polyester is made by condensing terephthalic acid with 1, 4-cyclohexane-dimethanol to form poly-1, 4-cyclohexylene-dimethylene terephthalate or the PCDT Polyester. As for PET Polyester, PCDT is processed for melt spinning.
Process of Manufacturing Polyester
Spinning
Polymer chips are melted at 500-518°F (260-270°C) to form a syrup-like solution. The molten polymer is then extruded through a spinneret and the filaments are subsequently drawn into the desired polyester fiber. Variations are introduced to obtain desired end results. Spinnerets having hole of different shapes such as round, trilobal, pentalobal, hexalobal or octalobal can be used for special effects like opacity, luster or its suppression, wicking, comfort or feel. Hollow fibers may be produced to make it lightweight and for providing greater cushioning or insulative properties. Crepe effect can be obtained through crimps. Certain additives may also be combined with the spinning solutions for specific properties. Delusterant can be added to make the fiber dull, a flame retardant may be added or certain other antistatic substance may also be included.
Drawing
After extrusion from the spinneret, the fibers are drawn or elongated, with the help of godet wheels. Depending upon the desired properties, the polyester fibers are usually drawn up to five times its original length. For higher tenacity, the filaments are drawn to a greater extent. When the fibers come in contact with the air, they solidify. Usually, the PET fibers are drawn hot as it produces more uniform fibers. PCDT fibers are drawn at higher temperature due to their higher melting point. During the drawing process itself, fibers may be textured which saves time, efforts and production cost and also gives greater quality control over the finished fibers. After the polyester yarn is drawn, it is wound on large bobbins or flat-wound packages, ready to be woven into material.
Types of Polyester Yarns
The polyester yarns have a wide range of diameters and staple lengths. The yarns are made basically as monofilament yarns, multifilament yarns and spun yarns.
Filament Yarns
PET Polyester is used to make filament yarns either in monofilament or multifilament forms. The direction and amount of twists are decided by the desired end use. The properties are also pre-determined. There are various types of such yarns. There is the bright, regular tenacity polyester yarn having light, stretch and sag resistance, used for sheer lightweight fabrics like tulle, voile and organdy. The regular tenacity semi dull yarn used for various apparels including lingerie. Its more dull version is used for shirts and blouses. Polyester yarns resistant to various chemicals, and micro organisms are produced from high tenacity fibers for such industrial uses as conveyor belts, ropes and nets etc.
Textured Yarns
These yarns are made of PET multifilaments. Texturizing is either done along with the drawing process or afterwards during throwing or texturizing process.
Spun Yarns
They are made of staple or cut PET or PCDT polyester fibers. The staple may be bright, semi dull or dull and tenacity may be regular, mid or high. It may be polished to reduce crimp and increase luster. It may either be spun alone or blended with other staple such as cotton, wool or rayon and then spun into yarn.
Application of Polyester
Polyester is used in manufacturing of many products, such as clothing, home furnishings, industrial fabrics, computer, recording tapes, and electrical insulation. It has several advantages over traditional fabrics as it does not absorb moisture. Its low absorbency also makes it naturally resistant to stains. Polyester clothing can be preshrunk in the finishing process. This makes it resist shrinking and it doesn't stretch out of shape. The fabric can be dyed easily, and is mildew resistant too. Textured polyester fibers are an effective, nonallergenic insulator, thus it is used for filling pillows, quilting, outerwear, and sleeping bags.
