It should not give rise to excessive foaming or turbidity in the solution or deposits on the fiber and machine parts. mercerization of fiber and is well established method for producing high quality fibers. In the traditional mercerization process, cotton yarn or fabric Then the remainder of the acid is removed from the fabric by washing. (b) Explain the working of multitubular pressure kier with the help of a neat diagram. it also gives the cloth a better resistance to multiple washings, keeping the colours bright and unchanged over time. Through the ages countless attempts have been made to alter the fiber, sometimes with a specific end use in mind and other times just as pure research. The mercerized sample is always more deeply dyed than the unmercerized. There are arrangements of squeezing rollers are guide rollers in each boxes. The important facts to remember are: Fiber is the fundamental unit in either yarn or in cloth. relatively circular when mercerised. Then the fabric is washed with hot water at 70Â°C by some rollers by spraying or counter consent process. Producing crepe effects by mercerization.-The principle of mercerization is sometimes employed to secure crepe effects in union goods, the mercerization attacking only one class of fibers or yarns, as for example the cotton threads introduced at regular intervals in a woolen structure. This process also depends on the buyer requirement. 1. If the shade is lighter than standard, the fabric is a lower degree of mercerization; and if darker, it a higher degree of mercerization. Savings of lye, washing water and steam are money for your account. The warps then passed through1-2boxes, containing cold water for cooling and rinsing. What are the benefits of Hot Mercerization? A ratio of dyed to undyed fibers can then be used to determine the degree of mercerization. So that the impregnation becomes properly. For light fabric, 45-65lbpressure is used and for coarse fabric 250lb pressure is used. Direct Blue No. Cotton fibers in the yarn bundle can be counted using a low power microscope. surface is smooth i.e properly mercerized. The machine is suitable to any kind of woven fabric (heavy, light, 100% cotton, linen, blends). A wetting agent is included in the mercerizing liquor which reduces mercerization time as a result of successful, uniform and rapid penetration of NaOH. The degree of cleanliness of the textile material is only determined by employing standard accepted testing methods and properly interpreting the data obtained. While mercerization had adverse effects on performance characteristics such as dry and wet breaking strength, tear strength, and flex abrasion resistance of HWM rayon fabrics, liquid ammonia treatment did not degrade these fabrics. This gives the seersucker effect. Mercerization involves exposing cotton to sodium hydroxide. The Mercerization is also applied to other cellulosic fibers such as Natural Linen, Hemp, the Bamboo, bringing significant benefits and quality improvements in manufactured products. Describe in detail the process of yarn mercerization. 15.19 Mercerization Uneven mercerisation – Improper tensioning, improper preparation of caustic solution, variation in time and temperature of treatment are the main causes of uneven mercerisation. By Igoo mercerized cotton was in extensive demand and the annual production and consumption have climbed every year since then. Fabrics are generally tested in order to determine the effectiveness of the mercerizing process and these tests are: The simplest test for mercerized cotton is to determine the number of twisted and untwisted fibers in a yarn bundle. The main... Alkali Degumming Alkalis hydrolyse protein by attacking the peptide bonds and are said to have severe damaging effect on protei... Waterproof Breathable Fabric: Waterproof breathable fabrics are one of the harsh weather fabrics that protect the wearer without hamp... Degumming of Raw Silk Degumming is at the heart of wet processing of raw silk. It is necessary then that mercerized yarns and fabrics should be signed in order to achieve greatest gloss or luster. Lowe (source: Wikipedia). The technical data and prescriptions are as follows: Prescription Â Â Â Â Â Â Â Â Â Â Â : 2.5 g/l Torozym NT, 2 g/l Schnellnetzer KE, 1 g/l, SpeedÂ Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â : 70 m/min, Table 2: The properties of the chemicals that were used in removing dressing, Table 3: The properties of the chemicals that were used in the bleaching process, Burner positionÂ Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â : Vertical â double side, Burner distanceÂ Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â : 8 mm, pHÂ Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â : 6 – 7, TemperatureÂ Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â : 60 – 65Â°C. Mercerization is a pre-treatment or finishing treatment of cellulosic materials with higher concentrated Alkali (NaOH) for short period at lower temperature. The fabric advances 5yds in contact with other rollers so that caustic soda can penetrate perfectly in fabric. (c) Name various tests of mercerization. The resistance to shrinkage values gave better results as the time period for application increased in the direction of the warp. Not only does the contraction of the fiber strengthen it, but also the thickening of the diameter due to the expansion already described stiffens the structure of the fiber. Brederek, K. , Changes of Optical Properties of Cotton Textiles Through Treatment with Liquid Ammonia and Sodium Hydroxide Mercerization, Veranderungen des Glanzes und der Farbtief, Changes in Luster and Depth of Color (in German), Textilvered. During the mercerization process, the thread or fabric is tightened and the crystals get into the parallel to the axis of the fiber inside of fiber and consequently, the links among the macromolecule chains (H Bridges, Van Der Wallâs forces) increase even more. THE REACTIONS THAT TAKES PLACE IN MERCERIZATION: Since concentrated sodium hydroxide (operational solution that includes chemicals) is used in mercerization process, the reactions that take place with the cellulose fibers are intermolecular reactions. As seen in Table 6, all the P values of plain, twill and dobby weave fabrics occurred 0.000 in terms of statistical significance in resistance to shrinkage in the warp except for the process time interactions of the dobby weaving fabric. The results of resistance to shrinkage obtained in this study were analyzed with SPSS 12.0 statistical data analysis program in the computer and their statistical significance was calculated. This clarity was not seen in the wet process and values close to each other were observed. Sick mink appear to rise from the dead in Denmark. Generally the range of twist factor is 2.2-3.0. The cross-section before mercerization is elliptical while it becomes As seen in Table 10, an improvement of 50 – 60% was seen in the direction of the warp compared to the raw fabric in the dobby weave. The threads or fabrics are subjected to tension during the finishing process for conventional mercerization. It imports gloss to the fibre, increases its hygroscopicity, strength and improves its dye affinity. Alternatively, the fabric (with about 10Â°Tw NaOH solution) may be passed through a recuperator where some more NaOH is recovered. List the main advantage of superwash wool: b. Thesis also discussÂ the change of trend, design and style among times andÂ know about how a technical person developed quality of product. The reason for that is that the fabrics gather a little bit in drying. Swelling therefore does not take place only on the fabric surface. MERCERIZATOIN (FOR LUSTRE) CAN BE CARRIED OUT IN TWO WAYS: By treating the cotton with NaOH solution, allowing it to shrink to the maximum content following by stretching to the original width (if cloth) or length (if yarn in the hank form). hollow part of fibre. The caustic actually rearranges the cellulous molecules in the fiber to produce these changes. The rest is history. I. Drying machine with contact drying system in which exit humidity control is carried out with Pleva equipment and which consists of 20 cylinders that work with steam. That is, there is no improvement in the resistance to shrinkage of those fabrics that are dried with an additional process. The faster the processes of mercerization, the better are the results of stability in the direction of the weft. When the fashions dictate a great vogue in silks, then mercerized cotton likewise leaps forward. This causes the fibers to swell, and their cross-section changes from kidney-shaped to round. Hence along with caustic we have to add some wetting agent. 52Â°Tw are not much sensitive. The properties of the fibre change by swelling. Keywords: Extraction, Hemicellulose, mercerization, Pandanus Odorifer, Retting. SANDOâs mercerizing machine with a clip-type stenter is capable of applying stronger tension on both warps and wefts compared to chainless types. This much Mercer discovered in 1844 and described in his application for a patent in 1850. Mercerization A third process often used with cotton fibers is mercerization, which changes the physical structure of the cotton fiber and thereby its physical properties and appearance. Textile Education is the largest textile blog over the net. As the next pictures show, there is a difference in the cross section of the fibre before and after mercerization. Tension pulleys are present due to variation of tension. The Advantages of Cotton. In case of scoured and bleached fabric, wetting agent is not important but using 0.1-0.5% gives better effect. The This has led some to present a pessimistic view of the media, to emphasize the ascendancy of ‘infotainment’ over ‘serious’ reportage and analysis of politics. US1482076A US616606A US61660623A US1482076A US 1482076 A US1482076 A US 1482076A US 616606 A US616606 A US 616606A US 61660623 A US61660623 A US 61660623A US 1482076 A US1482076 A US 1482076A Authority US United States Prior art keywords fabric thiocyanate treatment alkali solution Prior art date 1923-02-02 Legal status (The legal status is … Larger dyeing affinity 2. Wetting agent is used in caustic soda solution. Colors may be applied which dye the ordinary cotton faintly while giving the mercerized figures a very full, deep color. the mercerization is not even due to differential take up of warp and weft 2. Then the fabric is dried washing in cold water. Mercerization gives cotton woven cloth a silky luster, and is the foundation of many improved and beautiful finishes. Textile Points is a textile education blog. Each mangle is arranged to provide either a single or double immersion in the caustic liquor and two squeezes. About 30 g of cotton fiber was subjected to NaOH solution treatment for 4 h at room temperature. Higher strength is obtained after the process sequence due to: In this study, fabrics, that were woven by using 20/1 Open-end 100% cotton thread and three different weaving pattern, were chosen. Kidney shaped becomes almost circular (oval shaped) in X-section. When the fiber swells, its volume undergoes considerable changes; at maximum water absorption, the cross section of cotton fiber is increased by 40 to 50% with inconsiderable increase in length (about 1 to 2%). Considering the cost of cooling to 17 deg C (refrigeration) with only marginal advantages in swelling, mercerization nowadays is carried out at ambient temperatures The dwell time has not under gone any change and remains at around one min (50 Secs.) Hence the fibre Improved dimensional stability & physical compactness. The causes for carrying out grey mercerization are-. Impregnation time approximately 3 minutes and then allow tray is covered. Such fabrics are called crepons. The °Tw is measured by Complete fiber cleanliness is not easily achieved. Mercerization Conditions and Characterized by NIR FT Raman Spectroscopy in Combination with Multivariate Analytical Methods Heléne Almlöf Ambjörnsson,a,* Karla Schenzel,b and Ulf Germgård a Carboxymethyl cellulose (CMC) is produced commercially in a two-stage process consisting of a mercerization stage followed by an etherification stage. We see the best results at the conclusion of the trials with dry process. recovery of caustic is not easy on the grey fabric as it is full of impurities Its qualities are so excellent, however, that were it not for its value as a silk substitute it would still rank above ordinary cotton in its own right. During hot impregnation the lye penetrates faster and more evenly into the yarn core. Besides mercerization, he invented several styles of calico printing and prepared for the first time a sulphonated oil (known as Turkey red oil) ever since used in producing certain fast dyes. Mercerization is therefore an expensive chemical procedure. The reason for that is that, they gather a little bit in drying. Compression molding is a commonly used processing technique with advantages such as low cost, simplicity and relative predictability. sample is mercerised. The effect of different mercerization techniques on tactile comfort properties of woven cotton fabric has been studied. Moreover, using a wetting agent did not improve the stability. One of two rollers is geared to drive anticlockwise or clockwise. It describes textiles in comprehensive. stage of process sequence. In the direction of the weft, an improvement of 25 – 75% was observed depending on the time period similar to the plain weave. The possible variations in finish may be made even more numerous by the dyeing process. John Mercer.-The process of mercerizing cotton was discovered about 1844, by an Englishman named John Mercer, but he thought so little of his discovery that he took no patent on the process until 1850. THE CONDITION OR CONSIDERABLE POINTS FOR MERCERIZATION. Some of them are: when the grey fabric is mercerized some desizing and scouring takes place But suitable means it is possible to recover/ re-use 90-95% NaOH used in mercerizing. Fixed period Â Â Â Â Â Â Â Â Â : After the dyeing, they were held by rotating at the dock for 14 h. After fixing, the fabrics were washed with hot-boiling water and then dried at 120Â°C. * Ammonia recovery problem, leakages can be dangerous to the personnel involved. prof.k.b.krishna kumar presentation details this presentation has been devided into: introduction advantages of mercerization classification of mercerization what happens during mercerization parameters of mercerization effect of concentration effect of drying effect of teparature effect of tension temparature vs shrinkage shrinkage effects on lustre effects on … Mercerizing also gives cotton cloth increased tensile strength, greater absorptive properties, and, usually, a … For this reason, full impregnation cannot be obtained. Mercerized cotton is stained bluish black and the unmercerized cotton is remains white. The advantages of a high quality product produced with natural yarns, twists, sharp without pilling even after many washings, without pilling forever. If temperature and concentration of caustic soda increase up to a certain limit the tensile strength of cotton increases. The fiber starts out as a projecting hollow sheath and each night a new layer of cellulose is laid down on the inside of the sheath until about thirty layers are built up. Meanwhile, the role of wetting substances is great in the mercerization of raw fabrics especially. The retention compartment is not flooded. The wash water is feed into the chamber at the delivery end and is taken out at the entry end. These alterations increase sorption, tensile strength and luster of fibres. wrennal (J. soc. 01-0.5% HCl may be used to neutralize caustic soda. When the boll bursts and exposes these fibers to sun and air they dry up and collapse, becoming flatter and ribbon like with alternating left and right spiral twist every two or three turns. The first washing is with hot water and then cold water. With the modern textile finishing operations that are applied today, it is possible to provide cotton fiber with a structure similar to the superior properties of synthetic fibers. Not until the later eighties did mercerization become practical, and then for two reasons. Mercerization is the treatment of cotton yarns, fabrics and knit goods with cold, strong caustic soda liquor under tension. As the fabric is stretched in warp and filling directions, greater tensions produce greater luster and strength with improved dimensional stability. Tension mercerization:- This type of mercerisation is used to increase the luster of a fabric. Six measurements were done on each sample according to the standard of BS EN 26330 and the average of them was taken. Most of the goods were imported from Germany. The machine is suitable to any kind of woven fabric (heavy, light, 100% cotton, linen, blends) High flexibility to treat small and medium fabric batches (production speed up to 35 – 40 mt/ 1’). The fabrics are subjected to tension on a stenter on which most of the caustic is removed with hot water and then the remainder of base is neutralized in cold acid bath. Increase in alkali concentration had a continual positive effect for the samples mercerized at 20Â°C. good lusture property and mercerized effect as the degree of hydophilicity is If mercerization of material (yarn/fabric) is carried out in grey state i.e. Effect of Mercerization on Cotton goods in Woven and Knit Dyeing, Higher Production and its Remedies in the Germents Industry, Readymade Garments Export Business in Bangladesh, Social Compliance Manual for CAMIO USA Knitwear Limited, Social Compliance Issues in Apparel Sector, Application of Industrial Engineering in Sewing Floor, Effect of Different Count of Yarn on Grey Fabric Properties, Scope of Fashion Merchandising in Garment Industry in Bangladesh, Planning and Controlling Process of Professional Designer in a Design Studio, Causes of Fabric Wastages in Garment Manufacturing. As seen in Table 9, 60 – 70% improvement was seen in the direction of the warp compared to the raw fabric. in the fabric thereby becoming denser or fuller. Dy. But it is also used in a great number of so-called silk-mixed fabrics, such as silk-mixed mohair, silk-mixed alpaca, silkmixed woolen and worsted figured goods, silk-mixed worsteds for men’s wear, silk-mixed cottons, and so on. Col. 1977. A homogeneous swelling is produced in mercerization at 60Â°C, but the shrinkage in the fibers changes with the changing of the application time, thus stabilization will also change. It was bleached after the rotation period of 6 hour ended. Peroxide bleaching offers distinct advantages beyond good whiteness, as it is economical and flexible to use. On the other hand, solutions of sodium hydroxide whose concentration is about 29% (wt/vol), i.e. 25% solution of NaOH for 40-45 seconds. The mercerization of the original embryo or the desizing treatment of the original embryo or the mercerization of the refined cotton, their respective gloss, toughness, chemical activity and affinity for dyes, cannot help us choose the advantages and disadvantages. Ideally for mercerisation we use Some advantages of this mercerization over grey stage are: 1. The main purpose of the degumming process are to remov... What is Mercerization and Effect of Mercerization. Greater tension necessary to prevent shrinkage. The fabric is immersed in the solution for three minutes and then rinsed thoroughly. Length wise shrinkage of fabric occurs which minimize the weak links in the fiber. In hot mercerizing this is utilized, while in cold mercerizing it causes an energy consuming lye cooling process. So washing is very important after mercerization and its condition carefully should be maintained. form is passed through 25% NaOH solution and after a time of 40-45 seconds One of the known fiber properties of cotton is its softness. PHYSICAL CHEMICAL CHANGES THAT OCCUR DURING MERCERIZATION: When cotton fiber is brought into aqueous solution of sodium hydrose of 15Â°Tw (18%), the cellulose beings to swell immediately and in a few seconds the hair/ fiber is elliptical in X-section. Mercerization The process of mercerisation was developed by John Mercer (UK). No change was observed in the direction of the warp depending on the time period. Only some chemicals are required for mercerizing. Since the shrinkage in the fibers increases as the time period rises, the resistance to shrinkage in the weft appears to be higher. If the wash liquor is used in kier boiling the presence of sodium carbonate is an advantage; the only pretreatment necessary is filtration to remove the loose cotton fibers from the solution. It should not discolor the fiber permanently. In this condition the cloth is immersed in the caustic bath with the result that only the open figures are mercerized, the protected portions remaining plain cotton. During the last three shrinkage proceeds uniformly towards the center and the lumen does not recover its original size. It is found in such materials as sateens, silkoline, tubsilk, cotton taffeta, linings, dress goods, skirtings, and in embroidery and crochet yarns in its own name. Appearance is improved through increased luster, a deepening of the color and the production of a transparent look, the feel of the fabric is improved through a resulting soft hand and improved smoothness, and strength and elongation are also improved, along … the twedell meter. The threads or fabrics are rinsed a number of times after it has been subjected to sodium hydroxide. Not always is the whole fabric mercerized in piece-goods mercerization. This dependency is such that the resistance to shrinkage values increases as the period of holding increases. Since the shrinkage in the fibers increases as the time period increases, the resistance to shrinkage in the weft appears to be higher. The increasing public awareness and sense of social responsibility related to environmental issues have led the textile industry to manufacture products with improved environmental profiles. high. reflected is then compared. Lowe (source: Wikipedia). 2. In a good mercerization machine without chain, the time period required for the full impregnation of fibers with the caustic soda flotte is 12 s for dry fabrics and 20 s for wet fabrics. The mangles are of open type, enabling the bowls to be easily changed. The properties of the chemicals that were used in desizing and bleaching processes and other auxiliary chemicals were given in Table 2, Table 3 and Table 4, respectively. The liquor is usually heated by closed steam coils. When mercerized the walls of the lumen come closed to Dye absorption increases with the increasing caustic soda concentration up to 13%. Cell â OH Cell â OH + NaOH Cell â ONa + H2O Â Â Â Â Â Â Â Â Cell â ONa + H2O, 75%Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â 25%. Advantages of Ammonia mercerization * Less pollution. None of the imitations of silk has been more widely adopted than mercerized cotton. A high speed pad chain mercerizing m/c capable of handling fabrics like poplin and at the same time producing a high degree of luster. On the other hand in low twist yarn alkali enter easily and luster will be also good. Commonly 0.5-1% of wetting agent is used. It should able to reduce the surface tension of water. Sometimes the cloth to be mercerized is covered with a paste, leaving the cloth exposed only in certain places in the form of figures. Mercerized cottons likewise figure largely in upholstery goods, draperies, curtains, and coverings. Ideally, Controlled cooling of the stretched fabric. International Journal of Textile Science. Class Mercerization - Free download as Powerpoint Presentation (.ppt / .pptx), PDF File (.pdf), Text File (.txt) or view presentation slides online. Combined bleaching machine that makes hot bleaching and also has 2 prewashing and 4 final washing chambers. The distance between the two guide rollers can be altered according to the size of hank. The ratio of the two sets of data may be used to estimate the degree of mercerization. Ideally Mercerization is an alkali treatment process that is used to reduce lignin, hemicellulose, wax and oils that are present on the surface of fibers .