Eco safe natural dyes & application on textile materials

Transcription

1 T ECHNICAL ARTICLE Eco safe natural dyes & application on textile materials Dr. N. Tarafder Textile Consultant, Kolkatta. Present work deals with various application of natural dyes on substrates such as cotton silk and nylon. Different properties such as colour fastness, rubbing fastness and light fastness were evaluated and compared with the conventional dye textile materials. 1.0 INTRODUCTION Colour in ancient times was considered a spiritual necessity of equal importance to the physical needs of food. So in every civilization from remote ages to the present day the art of dyeing has played an important role in adding beauty to the world. India was once known as a leading source of the earliest natural origin which is classified as vegetable, mineral or animal and were abundantly used by primitive people and were in vogue until the middle of the nineteenth century. Prior to the invention of synthetic dyes in 1856, all colouring matters were extracted from the naturally available materials. Though India was known as a leading source of the earliest natural dyes, but interest in natural dyes declined as efforts were directed towards developing and manufacturing new synthetic dyes. Dyeing makes an important contribution to fabric decoration by producing many beautiful colors and the colour harmonies obtained by a combination of various dyeing methods. Soon the synthetic dyes started replacing the natural ones as the synthetic dyes were brighter, faster, intensive and cheap. So people lost irrevocably many of these old dyeing skills. But, in the last phase of the century, mankind has become afraid of a series of synthetic dyes which have some carcinogenic effect on human skin and also due to the environmental pollution they cause-prevention of both of which is dead serious. These factors have revived our interest once again towards the use of natural dyes and we have decided to trace back our steps and start producing those once again. According to the Society of Dyers and Colourists, natural dyes are those colorants which are obtained from plants or animal resources with little or no chemical treatment. Most of these are mordents dyes though some acids, vats and directs are known. There is only one basic dye known as Berberis Aristata and there is no sulfur, azoic and reactive natural dyes. A number of natural dyes, however known were black, dark blue, green, scarlet and madder. These colours were obtained from flowers, leaves, barks, berries, stalks and roots of different plants. Natural dyes require mordents to give substances, which combines with dye to render it insoluble. This is generally a metallic salt which has an affinity for both the coloring matters and the fiber. October 2009 Man-made Textiles in India 355

2 2.0 NATURAL DYES Among all, plant world furnishes the principal sources of natural dyestuffs. A number of natural dyes known for long are black, yellow, dark blue, green, scarlet and madder, which were obtained from flowers, leaves, barks, berries, stalks and roots of different plants. Again, dyestuffs of animal origin are also obtainable like cochineal and lac dyes. Some mineral dyes also come under this head. A pale purple dye mauve obtained from crude aniline was the first to be manufactured synthetically. Barring on the basis of origin, the natural dyes are also classified according to their substantive, chemical properties, colour production, etc. Moreover, research work from various institutes confirmed that almost all the natural dyes applicable on silk belong to the acid mordents class, only indigo belongs to the vat dye class. 1. Others: Onion Peels, Mushrooms, Weid, etc. 2. Mineral Origin: Iron Buff, Mineral Khakhi, etc. 3. Animal Origin: Lac (Secretion of lac/kaksha insects) Hence, modern dyers are intending to apply natural dyes on use of different metallic salts as mordent to get different shades since fastness properties of these dyes without mordent are found poor in most cases. 2.1 ADVANTAGES OF NATURAL DYES 1. The colors are gentle, soft, subtle and create a restful effect. 2. The color is enhanced with age and mellows to increase beauty. 3. There is charm and challenges due to the uncertainty of the dyeing results. 4. They are used in the conservation and repairs of historic textiles. 5. Better bio-degradability and generally higher compatibility with the Environment and also act as manure enriching the soil. 6. They also have lower toxicity and are non-allergic and non-carcinogenic. 7. They save energy because the raw materials are not from petroleum. 2.2 LIMITATIONS OF NATURAL DYES 1. It brings an over exploitation of nature due to commercialization. 2. Natural resources are not available in all the countries. 3. There is difficulty in the collection of the dye. 4. There is a lack of standardization. 5. Cost factor may have to be considered. 6. Unsuitable for synthetic fibers. 7. Problems in the process complexity and reproduction. 8. Limitations in the shade range. 3.0 CLASSIFICATION OF THE NATURAL DYES Natural dyes are classified into two groups, namely substantive and adjective dyes. The substantive dyes required no pre-treatment to the fabric (i.e Indigo, Turmeric, etc). The adjective dyes can only dye the material mordent with metallic salts or with the addition of a metallic salt to dye bath (e.g logwood, Madder,etc). Substantive dyes can further be classified as direct (for Silk, i.e Safflower) acid (for Silk, i.e Saffron, etc) basic (for Silk, e.g Barberine). Natural dyes can also be classified into monogenetic and polygenetic dyes. The monogenetic type produce only one color irrespective of the mordent applied along with dye or present on the fiber where as the polygenetic dyes produce different colors according to the mordent employed (i.e Logwood, Alizarin, Fustic, etc). Natural dyes can be further classified into two groups on the basis of their origin into dyestuff of animal origin (i.e Lac, dyes, etc). A detail classification is given as follows: 3.1 AS PER ORIGIN Vegetable Origin Fruits: Microbalance (Harda/Harituki), Annato Seeds. Leaves: Indigo, Lowsonia, (Henna), Eucaliptus, Neem, etc Flowers: Marigold (Genda), Sunflower, Harishnagar (Silui), etc. Root/Stem/Bark: Madder (Manjishtha), Kattha (Cutch), Turmeric (Haldi), Aalroot,etc.), Cochineal, etc. 3.2 AS PER CHEMICAL ORIGIN 1. Indigoids: Blue and Purple dyes(indigo, Woad, Tyrian, Purple). 2. Anthraquinones: most of the important Red dyes(madder, Lac, etc). 3. Alpha Napthaquinone: Henna, Walnut. 4. Flavones: Most of the Yellow dyes (Weid, Tesu, Kumkum, Onion). 5. Di-hydroporan: Logwoo, Brazilwood. 6. Anthrocynidin: Bignoia Chica, Awobanin. 7. Caratinoids: Carrot, Sindur, Kesar. 8. Polyhydric Phenol: Brown, grey, Black dyes (Pyrabolan, Pomegranate). 3.3 AS PER METHOD OF APPLICATION 1. Mordant dyes: Most of the natural dyes (Madder, Logwood, Cochineal). 2. Acid dyes: Saffron. 356 Man-made Textiles in India October 2009

3 3. Direct dyes: Turmeric, Harda, annatto, Safflower. 4. Basic dyes: Barberine. 5. Vat dyes: Indigo, Wood, tyrian, purple. 6. Disperse dyes: Henna. 3.4 EXTRACTION OF NATURAL DYES 1. Technology for production of natural dyes could vary from simple aqueous extraction to complicated solvent system to sophisticated super critical fluid extraction technique depending upon the product and purity being achieved. 2. For the production of natural dyes for textile applications, the aqueous extraction with alkali is the most common methods but this may change the tone or hue of the actual color. So, it is better to extract the dyes with water, although the % yield is less in this case as compared to alkali extraction. 3. The raw materials for the production of natural dyes is mostly vegetable matters in the form of seeds, leaves, roots and barks of the plants. 4. Some of the seasonal flowers like Palas, marigold, etc, can produce excellent color, but aqueous extraction of these color are to be used within 24 hrs, other wise due to fungus growth in the color value gradually disappears. 4.0 APPLICATION OF NATURAL DYES ON COTTON 4.1 MORDENTING It is the process of application of aqueous solution of any mordant agent on the fabric to improve the affinity of these dyes to fibers to be used before dyeing, after dyeing or during dyeing as applicable to or needed. Mordent combines with the fiber and dye, by forming a link between fiber and dye. Examples of mordants are oils (T.R.O, Palm Oil, Olive Oil, Coconut Oil), Tannis (Tanic acid, Sumach) and Metallic salts (Alum, Aluminium sulphate, Copper sulphate, etc.) 4.2 APPLICATION Cellulose fiber have no direct affinity to natural dyes. So, at first, mordant has to be made. The final mordent material is treated in the aqueous extract of the natural dye solution at specific temperature, for specific period. The dye is absorbed and fixed with the help of the metallic ions, forming dyemetal ions lakes. The lakes obtained by the reaction between the metal ions attached to the fibre and ionic bonds or bicoordinate bonds mainly form mordant natural dyes. After dyeing the materials are required to be rinsed with cold water. The colors are built up according to the use of the selective metallic ions from different metal salts. The final dyed material should always to be washed with non-ionic liquid detergent to remove the surface colors and to improve wet fastness, instead of ordinary detergent powder available in the markets, which contains Na- compounds or soda. 4.3 DYEING BY SOME NATURAL DYES MADDER Mordanting is done by 10% tannic acid at 60 0 C for 1 hr, and subsequently treated with 50% alum at 60 0 C for 1 hr. Dyeing is performed with 100% Madder at C for 1 hr and over dyed with 0.25% of Indigo usual additives (salt, caustic and hydrosulphide) in and out. The process is repeated 4 times COCHINEAL Mordanting by TRO and 28 gpl Na-phosphate treatment for 1.5 hr under steam pressure at C to be done and repeated oiling followed by soaking with 6% tannic acid at C for over night and subsequently treated with 20% alum with 32 gpl soda and 50 gpl ammonia at 40 0 C for 1hr and finally rinsed in 10 gpl Na-phosphate solution. Dyeing is performed with 25% Cochineal at C for 1hr and over dyed with 1 gm of Indigo with additives (5 gm NaOH & 10 gm Hydrosulphite) WEILD Mordanting is done by 6% tannic acid at 40 0 C for 1 hr, and subsequently treated with 20% alum with 32 gpl soda ash and 50 gpl ammonia at 40 0 C for 1hr. Dyeing is performed with 300% Weild at C for 1hr and over dyed with 0.3 gm of Indigo with usual additives (5 gm caustic and 10 gm hydrosulphite) for 5 mins dip AAL ROOT OR BARK AND COW DUNG These are used to get red and maroon shade for cotton products. Aal Root contains the main color pigment Morindone. Other pigments presence in Aal Root are Asperuloside, Damncanthal, Glycosides, Morindiol, Morindie, etc. Aal Root belongs to mordent class of dyes. But simply mordant it cannot be fixed on cotton, it needs a special process of traditional system of dyeing. Which are as follows: Treatment with oil Treatment with cowdung Treatment with alkaline solution of burnt wood ash Dyeing with Aal Root powder. 1.5 kg yarn is soaked in water, squeezed and then treated with half kg of caster oil for min. For 1.5 kg of yarn, about 2-3 kg of cowdung is necessary. Thick paste of fresh cowdung is prepared with water and oil treated yarns is impregnated with cowdung paste. Then is dried under sun. A clear decanted alkaline solution is prepared by boiling charcoal ash(burnt wood). For 1.5 kg of yarn, about 25 liters of alkaline solution is prepared. The dried yarn after impregnating with cow dung is further treated with the said alkaline solution for mins and then dried under the sun, till brown color is developed in the yarn within 8-10 days. Aal dye solution is prepared by boiling the Aal root or bark with October 2009 Man-made Textiles in India 357

4 water and the above said treated yarn is dyed with the Aal root solution until the desired color of the yarn is developed, dyeing process is repeated 2-3 times till the desired shade is obtained days for this dyeing process from grey yarn to dyed stage, enhance the dyeing cost per bundle of 4.0 to 5.0 kg of yarn. Again, the dyeing process it self involves harsh treatment like oiling and cow dung treatment, thus only coarse yarn up to 20s count are dyed, as fine yarn cannot withstand such harsh actions. 5.0 A LIST OF PLANT MATERIALS 1. Shades of Orange: Sassafras (Leaves) Onion Peels Lichen (Gold) 2. Shades of Brown: Sumac (Leaves) Walnut (Hulls) Tea Bags (A light Brown) Juniper Berries Coffee Grinds Acorns (Boiled) 3. Shades of Pink: Straw Berries Cherries Rasp Berries (Red) 4. Shades of Light Green: Lily-of-the-Valley (Leaves) 5. Shades of Red: Dandelion (Root) Beets (Deep Red) Rose (Hips) Red Onion (Skins) Chokecherries Madder 6. Shades of Blue-Purple: Red Cabbage Elder Berries Grapes Blue Berries Cherries (Roots) Black Berries (Strong Purple) Japanese Indigo (Deep Blue) Red Cedar Root (Purple) Red Maple Tree (Purple) 7. Shades of Gray Black: Iris (Root) 8. Shades of Red Purple: Poke Weed ( Berries) 9. Shades of Green: Spinach Leaves Black-Eyed Susans Grass Nettle Plantain Roots 10. Shades of Yellow: Red Clover (Whole Blossom, Leaves & Stems) Alum, Mordant, Gold Yellow Cone Flower (whole flower Head) Chrome Mordant, Brass to Green Brass, Onion (Skin), Willow (Leaves),Queen Anne s Lace, Burdock, Celey (Leaves), Golden Red (Flowers), Sumac (Bark), Weld (Bright yellow), Cameleon Plant (Golden), Osage Orange, Dandelion flower, 11. Shades of Black: Sumac (Leaves) 12. Shades of Peach: Brown Flowers, Virginia Creeper (All Plants), Alum Mordant, Peach 6.0 APPLICATION OF NATURAL DYES ON SILK The following is the list of natural dyes which can be applied on silk:- SL. COLORANTS BOTANICAL EXTRACTED NAMES COLORS 01. Logwood Haematoxylon Black Campechianum 02. Indigo Indigofera Blue Tinctoria 03. Madder Delonich Regia Deep Orange 04. Rangan Ixora Aurantiaca Red 05. Turmeric Curcuma Longa Yellow 06. Tea Leaf Camellia Siencis Blackish Brown 07. Anar Punican Granetum Brownish Pink 08. Aparajita Clitoria Tarnatea Blue 09. Arjuna Bark Terminalia Arjuna Reddish Pink 6.1 MORDANTING Natural dyes require mordant to give substance which combines with dye to render it insoluble. This is generally a metallic salt which has an affinity for both the coloring matter and the fiber. Generally substantive natural dyes do not require mordant unlike the adjective ones. Some common mordant are:- FeSO 4, MgSO 4, (SO 4 ) 3, Al 2 (SO 4 ) 3, CaCl 2, ZnCl 2, MnCl 2, 358 Man-made Textiles in India October 2009

5 The mordant may be applied in various ways: 1. Before the dyeing 2. After the dyeing 3. Simultaneously in the same bath 4. Both before and after the dyeing 6.2 APPLICATION OF JATOPHA DYES Jatropha Curas is a plant that can be grown on any kind of soil that belongs to the family Euphorbiaceac. Plain woven silk fabric was selected because of its even dye uptake and lustrous appearance. Myrobalan was used as a fixing agent and mordant. The chemicals used for fixing colors on silk fabric were copper sulphate, potassium dichromate, ferrous sulphate, and a combination of two mordant, stannous chloride and magnesium chloride. De-gumming of the silk fabric is first done at 95 0 C for 1 hour with the standard receipe. The samples were then pretreated with the solution containing 20 gms of Mybrolan per liter of water. The material to liquor ratio was 1:20. The samples were treated in the solution for 24 hrs at room temperature and then exposed to sunlight for 3 hrs. 6.3 OPTIMIZATION OF DYEING VARIABLES. It was found in the trial method that the best method for dye extraction suitable for dyeing fabric was the acidic method. Post mordant dyeing method gave good results than premordant and others at 30 minutes mordant. The Jatropha seed dye extract produced the best colors on 1 g of each silk samples by using 0.8% CuSO 4, 0.4% FeSO 4, 0.5% Potassium Dichromate plus 0.5% combination of Stannous Chloride. After extracting the Jatropha color, 1ml in 100ml of conc HCL in H2O is preferred. The temperatural is raised to 95 0 C and carried out for 1 hr with the extract and sample. The colors obtained were brownish khaki, black, greenish khaki, and light yellow with copper sulphate, ZnSO 4, K 2 and Stannous+Magnesium Chloride, respectively. 6.4 EVALUATION OF COLOUR FASTNESS TEST Four colour fastness tests for silk fabric were conducted, like colourfastness to perspiration, rubbing, sunlight, and washing. These tests were conducted on five dyed silk samples according to BIS Standards, using geometric grey scale. The rating was done by panel of judges. The results of colour fastness tests were statistically analyzed, using arithmetic means. Those indicated that colour fastness to acidic perspiration of all four colours was good to excellent. Black had the best fastness followed by light yellow, greenish khaki, and brownish khaki in descending order. Colourfastness to alkaline perspiration of light yellow and greenish khaki was good to excellent. The grey and brownish khaki in descending order was revealed. The dry rubbing fastness of brownish khaki light and grey colours showed good to excellent fastness. Greenish khaki colour had fair to good fastness. The brownish khaki colour at the best fastness followed by yellow grey and greenish khaki in descending order was noticed. With regard to wet rubbing, the results indicated that light yellow, greenish khaki and brownish khaki good to excellent fastness and grey had the fair to good fastness. Among the four colours, light yellow had the best fastness followed by greenish khaki, brownish khaki and grey. When the samples were subjected to sunlight test, the results proved that brownish khaki, black, greenish khaki and light khaki had good fastness. Among the four colours, brownish khaki had the best fastness followed by light yellow, grey, greenish khaki in descending order. The results of colourfastness to washing proved that light yellow and greenish yellow had good to excellent fastness. The brownish khaki and grey colours had poor to fair fastness to washing. The light yellow colours had the best fastness, followed by greenish khaki brownish khaki, and grey in descending order. Thus from the above findings, it can be concluded that the dyes extracted from the Jatropha seeds have a range of bright, soft, even and lustrous colours on silk fabric. The important advantage of this dye is its adaptability to small scale and cottage industries. 6.5 TURMERIC DYEING ON ERI SILK After de-gumming of the samples, four different samples were treated with the metallic salts separately using the selected mordant. Treatment was done with 5% of mordant at 1:30 (M:L) at 60 0 C for 30 min for each chemical. After that, the mordant samples were labeled as TA1 (AlSO4+Dye), TA2 (SnCl2, 2H2O+Dye), TA3 (K2Cr2O7+Dye), TA4 (Fe2SO4, 7H2O+Dye). The mordant silk samples were transferred to the dye bath. The temperature of the bath was gradually increased to 60 0 C for 20 min. After that, the samples were taken out of for adding sodium carbonate (8%). The solution was Stirred well and the fabric was immersed in the dye bath and the process was continued for 10 min. After 30 min the samples were taken out and rinsed with soft water and soap and again rinsed, dried and ironed. The shades obtained were bright yellow for alum, bright orange for stannous chloride, brownish for K 2 and olive greenish for ferrous sulphate. The samples untreated with mordant obtained yellow colour. 6.6 COLOUR FASTNESS All mordant samples showed noticeable colourfastness to washing. About 80% respondents rated the changes as negligible while treating with stannous chloride and 60% termed negligible in the case of untreated samples and those treated with alum. Like wise 19% respondents rated as slight changes in the samples and those treated with alum. Like wise 19% respondents rated as slight changes in the samples treated with stannous chloride and 39% remarked as slight change for untreated samples. Only 25 of the respondents termed it as noticeable change in the samples October 2009 Man-made Textiles in India 359

6 treated with K 2 and 6% judges remarked as noticeable change in the case of untreated samples. So far as the colourfastness to sunlight is considered, the observations show that the 72%, 74%, 80% and 71% of the judges considered negligible changes in the samples treated with FeSO 4, K 2, SnCl 2 and alum compared to 60% of them who considered negligible changes in the untreated samples. For wet crocking, the observation reveals that 76%, 64%, 71% and 68% of the judges considered negligible changes in the samples treated with FeSO 4, K 2, SnCl 2 and alum compared to 59% of them who considered negligible changes in the untreated samples. For dry crocking, it is revealed that 80%, 81%, 76% and 74% of the judges considered negligible changes in the samples treated with mordant, where as 67% considered negligible changes in the untreated samples. 7.0 APPLICATION OF NATURAL DYES ON NYLON 7.1 STUDIES ON DYEING NYLON WITH RATANJOT DYE Ratanjot (Onosoma Echoides) has been traditionally used as a good colourant and the bark of the roots contain several naptha quinine pigments which gives a violet-red colour. The main pigment is believe to be alkaline and is insoluble in water but has been used to dye wool, silk, nylon and cotton at 40 0 C with the addition of alcohol for one hour. With alum, colours from lialic to red and iron tones of grey and violet has been obtained. As alkaline is a napthaquinone based dye, theoretically it is expected to behave as disperse dye. 7.1 METHOD OF DYEING The dyes of this group must be brought into a state of fine suspension in the dye bath, which does not present any particular difficulty. The dye is stirred with times its weight of water at 50 to 60 0 C and is allowed to stand for 10 min with occasional agitation. If the mixture is not sufficiently fluid for straining, more warm water may be added. It should be emphasized that boiling water should not be used for nor pasting be carried out in presence of highly concentrated surface active auxiliary products. Lumps may be formed during dispersion which do not disperse and filtration through a sieve before addition to the dye bath is most desirable. Before addition of dyestuff approximately times of a synthetic dispersing agent per 100 gal, should be put into the liquor. Those products assist in maintaining a stable suspension and also increase the stability of the pigment in water. Thus decreasing the affinity of the fiber and acting as a retarding agent. When the dye bath is prepared the goods, which have been scoured previously are entered cold and the temp is raised slowly to between C and the dyeing is continued at that temp for 1 hour until the shade is level. If mordant is required it can be done before dyeing, after dyeing or during dyeing. Here alum was added as mordant. 7.2 DYEING OF NYLON WITH LAWSONE AND JUNGLONE Purified dyes were used to dye Nylon with Lawsone and Junglone. These dyestuffs are very simple in structure and are actually isomers so that it was possible to study the effect of substitution on dyeing mechanism. The approach was to understand the dye fiber interaction when the dye bath is in a state of equilibrium. The dyes basically behaves as disperse dyes like Ratanjot dye. The preparation of material, method of dyeing and mechanism of dyeing are the same as Ratanjot dye. The structure of the dyestuffs is Lawsone, Henna and Junglone, Walnut. 7.3 DYEING OF NYLON WITH BARBERINE Barberine, the dye pigment present in the roots of Barberry (Barberis Aristata) has a bright flourescent yellow colour and is the only known material basic dye. This is an alkaloid accompanied by its hydroxylated derivatives, like Barberuine, Palmatine, Columabamine, Barbamine and Oxycanthene. The Barbexne base is unstable and assumes the aldehyde form Barberinal, where as it salts are derived from ammonium form. Preparation of material is known as that of the other classes mentioned earlier. The dye bath contains 227 g of acetic acid per 455 L of water. The goods are put in cold and the temp is raised gradually to 82 0 C. The dyestuffs solution is added in proportion during the dyeing operation. 8.0 CONCLUSIONS Unlike the non-renewable petrochemical source of synthetic dyes, the natural dyes are renewable, biodegradable and eco-friendly, non-hazardous and its wet and light fastness is satisfactory but the present production of natural dyes all over the world is only 1% of the synthetic dyes consumption because they are difficult to standardize the receipe and method. The use of natural dyes and applications of natural dyes are sometimes expensive and time consuming process. The colour fastness of cotton materials dyed with natural dyes showed rating as moderate to good in the case of Turmeric. The rubbing fastness of all dyeing showed moderately to good except in the case of Turmeric and dry condition in rubbing proved better than wet fastness. Light fastness for all the dyed materials remained poor even after treatment with a cationic dye-fixing agent. The dyes extracted from the Jatropha seeds have range of bright, soft, even and lustrous colours on silk fabrics. The important advantage of this dye is applicability to small scale and cottage scale industries. The dyeing of Eri silk with Turmeric dyes by treating with different mordant improved the colour fastness properties. Natural dyes may be regarded as myth since synthetic chemicals assist their applications. Dyeing Nylon with natural dyes exhibited exceptional fastness to light and washing. The colours are succeptble to light 360 Man-made Textiles in India October 2009

7 fading but are fast to washing. However, there is a great scope to improve all the fastness properties of the fabric dyed with natural dyes by optimizing the conditions of dyeing, i.e ph, temperature, time, etc. REFERENCES 1. N. Singh, S. Jalan & K. G. Gupta, Colourage, Vol. 50, No. 8, A. Agarwal, A. Sarge & K. C. Gupta, Colourage, Vol. 38, No. 3, A. Gogoi, S. S. Ahmed & N. B. Barua, Ind. Text. J. Vol. 107, No. 11, Aug W. B. Achwal, Colourage, Vol. 45, No. 1, March M. D. Teli & J. Singh, J. Text. Association, Vol. 58, No. 5, Brain Glover, J.S.D.C., Vol. 114, Jan Gogoi & B. Kalila, Colourage, Vol. 46, No Gulrajani et. al., Vol. 46, No. 7, W. B. Achwal, Colourage, Vol. 42, No. 2, Nov A. Gary, S. Shinde, Colourage, Vol. 38, No. 3, March N. C. Pan, A. Dey & K. K. Mahalanabis, K. K. Text. Dyer & Printer, Vol. 3, No. 3, A. A. Ansari, B. D. Thakur, Colourage, Vol. 47, No. 7, July D. Radhika & M. Jacob, Ind. Text. J. Vol. 110, No W. Anita Devi, A. Gogoi & D. P. Kharikar, Ind. Text. J. Vol. 110, No. 12, Man-Made Textiles in India ADVERTISEMENT TARIFF COLOUR ADVERTISEMENTS TECHNICAL DATA Space Size (cm) Rate (Rs) Overall Size : 28 cm x 21.5 cm (Per insertion) Print Area : 23 cm x 17.5 cm Back Cover 23 x , Type of Printing : Offset Inside Cover 23 x , Advertisement Material : Positives with Inside Full Page (2 Colours) 23 x , Progressive Inside Full Page (3 Colours) 23 x , Proofs Inside Full Page (4 Colours) 23 x , Inside Double Spread (4 Colours) 28 x 38 8, BLACK & WHITE ADVERTISEMENTS REBATE Inside Cover 23 x , % Rebate on 6 to 9 Insertions Inside Full Page 23 x , % Rebate on 10 to 12 Insertions Inside Half Page (Horizontal Only) 11 x , The Synthetic & Art Silk Mills Research Association, (SASMIRA), Sasmira Marg, Worli, Mumbai October 2009 Man-made Textiles in India 361

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