SCOPE OF NATURAL DYES IN PRESENT SCENARIO

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1 SCOPE OF NATURAL DYES IN PRESENT SCENARIO S. Swetha Shanmathi 1, S. Geetha Margret Soundri 2 1 Student, Department of CDF, Sri Krishna Arts & Science College, Coimbatore 2 Professor and Head, Department of CDF, Sri Krishna Arts & Science College, Coimbatore ABSTRACT The usage of natural dyes has been decreased due to the invention of synthetic dyes. Natural dyes should make a comeback into the mainstream fashion. The production of textiles using synthetic dyes over years has contributed to significant environmental problems. In order to overcome the problem natural dyes are great solution to counter the issue and run business in an ethical way without causing much negative impact on the environment. Natural dyes are dyes or colorants derived from plants, invertebrates, or minerals. In recent years, the demand of natural dyes in textile, food processing, cosmetic and pharmaceutical industries has been rapidly increased all over the world due to eco-affable nature and all this happened due to the excessive use of synthetic molecules in the last two centuries. However, the technology of extracting and utilizing natural dyes in the modern textile industry is relatively new and is still being improved upon. In India, textile manufacturers are not yet finding proper enticement in switching over to natural dyes for being more expensive than their synthetic counterparts. In this review paper we are going to discuss about the scope of natural dyes in present, sources and extraction, advantages and disadvantages of natural dyes. Keywords: Natural Dyes, Extraction, Eco System, Synthetic Molecules I. INTRODUCTION Natural dyes are dyes derived from animal or plant material without any chemical treatment. They are obtained from sources like flowers, leaves, insects, bark roots etc.; however, they are not readily available and involve an extraction process. In prehistoric times, natural colorants were usually obtained from berries, blossoms, barks and roots. [1] They were applied to the fibre without any pre-treatment of the dye-material or the textile. Lately there has been increasing interest in natural dyes as the public becomes aware of the ecological and environmental problems related to the use of synthetic dyes. [2]A few examples for historical natural dyes are as follows: Indigo: One of the most important and popular dyes from ancient times till today. It is obtained from the leaves of Indigfera turquoise. Logwood: The tree is fairly large and the freshly cut wood is colourless until it is exposed to air. Madder: The valuable dye pigment that give Turkey Red Colour. 74 P a g e

2 II. SCOPE OF NATURAL DYES In the present scenario, due to the excelling advantages of natural dyes, it is becoming an enticing option over synthetic dyes. These are as follows: Biodegradable Non-toxic Environment Friendly Aesthetically appealing resulting in employment generation and utilization of wasteland. Easy extraction of colours by boiling the plants, berries, leaves, bark or flower heads in water. Focus towards the utilization of the vast diversity of natural resources of colour pigments for their use in food materials, pharmaceuticals and textiles, in place of their synthetic counterparts. This trend is aimed at safeguarding human health as well as protecting and prolonging life on Earth. Detailed scientific studies with natural dyes have established that in most cases their properties are comparable to those of synthetic dyes. Therefore, if natural dyes have to be commercialized, they need to conform to the same stringent standards of performance that are applied to synthetic dyes. It thus follows that much more research and developmental effort needs to go in this area. The technology of extracting and utilizing natural dyes in the modern textile industry is relatively new and is still being improved upon. [3] In India, textile manufacturers are not yet finding proper enticement in switching over to natural dyes for being more expensive than their synthetic counterparts. Synthetic dyes have replaced almost all the natural colouring matters. However, the art and craft of producing natural dyed textiles is being practiced in every corner of the country by a handful of expert crafts-persons. This may be Bandhani Sarees in Orissa and Rajasthan, Multani sarees in Rajasthan, Gujrat and Madhya Pradesh, Kalamkari Printing in Bihar and Andhra Pradesh. III. SOURCE AND EXTRACTION Natural dyes are derived from natural resources and based upon their source of origin, they are broadly classified as plant, animal, mineral, and microbial dyes although plants are the major sources of natural dyes. The different sources of origin is briefly listed below. 3.1 Plant Origin Historically, plants have been used for the extraction of a majority of natural dyes. Various plant parts including roots, leaves, twigs, stems, heartwood, bark, wood shavings, flowers, fruits, rinds, hulls, husks, and the like serve as natural dye sources. A renewed interest in natural dyes has increased their commercial availability. Some such important dyes reported in many publications are listed below Blue Dyes Indigo is the only important natural blue dye. Leaves of the plant indigoferatinctoria are the best source of this dye. This very important dye popularly known as the king of natural dyes has been used from ancient times till now for producing blue colour and is today most popular for denim fabrics. The colouringmatter is present in indigo plant leaves as a light yellow substance called indicant 75 P a g e

3 3.1.2 Red Dyes There are several plant sources of red natural dyes. A few popular sources are listed below Madder Madder is the red colour producing natural dyes from the plants of various Rubia species. The dye is obtained from the roots of the plant. It is also popularly known as the queen of natural dyes. Rubia cordifolia is known as Indian madder, manjishth, or manjeet and its colouring matter is a mixture of munjistin and purpurin. In addition to roots, dye is also present in the stems and other parts of the plant.dye is usually extracted by boiling dried root chips or stem pieces with water but sometimes, these are merely steeped in cold water for few hours. As it is a mordant dye, it produces brightlycoloured insoluble complexes or lakes with metal ions present on the mordant fabric. [4] Alum is widely used to get pink and red shades Brazil Wood/Sappan Wood A red dye is obtained from the wood of Caesalpina sappan, a small tree found in India, Malaysia, and the Philippines which is known as sappan wood or Patang.. Textile materials can be dyed to get the red colour with or without the use of alum mordant. A combination of this dye with turmeric produces orange shades and a deep maroon colour is produced with catechu. 76 P a g e

4 Morinda The root and bark of the tree Morinda citrifolia growing in India and Sri Lanka is used for getting red shades. Maximum colouring matter can be obtained from the 3 to 4-year-old tree. Mature trees have very little dye. Dye is extracted from the chipped material with water after a preliminary wash to remove free acids. [5] Various shades including purple and chocolate can be produced with the use of mordants Safflower Safflower is an annual herb known to have originated in Afghanistan. It is mainly cultivated for oil from its seeds which are rich in polyunsaturated fatty acids. The safflower florets were traditionally used for extracting dye which was valued for its bright cherry-red colour. It contains two colouringmatters, a water-soluble yellow present in abundance (26 36 %) which was not used as a dye and the scarlet red water-insoluble carthamin present only to the extent of %. Safflower has been employed to give cherry-red direct dyeings on silk and cotton. The dye is extracted from dried safflower florets by continuously washing it with acidulated water to remove all the water-soluble yellow colouring matter. The washing and light fastness of the dye is poor. Yellow dye has now also been used to dye mordant cotton. 77 P a g e

5 3.1.3Yellow Dyes Yellow dyes are available from several plant resources. Some of the prominent sources are listed below Turmeric Turmeric is a well-known natural dye. The dye is extracted from the fresh or dried rhizomes of turmeric. The dye present is chemically curcumin belonging to the Diaroylmethane class. It is a substantive dye capable of directly dyeing silk, wool, and cotton. The shade produced is fast to washing but its fastness to light is poor. [6] Turmericdyeing can be over dyed with indigo forproduction of fast greens Saffron Saffron is an ancient yellow dye belonging to the family Iridaceae and is obtained from the dried stigmas of the plant Crocus sativus. It is grown in the Mediterranean, Iran, and India, and used for cooking as well as medicinal purposes. The dye is extracted from the stigmas of flowers by boiling them in water. It imparts a bright yellow colour to the materials. It can directly dye wool, silk, and cotton. Alum mordant produces an orange yellow known as saffron yellow Annatto Annatto Bixa orellana is a small tree belonging to the family Bixaceae. The tree is known for the yellow orange dye obtained from its seeds. It is extensively used for the dyeing of cotton, wool, and silk and also used for colouring butter, cheese, and the like. The pulp is rich in tannin. The alkali extraction method is used for extracting dye at boiling conditions. It produces reddish orange shades on cotton, wool, and silk. 78 P a g e

6 Barberry The barberry plant roots, bark, and stems are used to extract the dye. The main constituent of the dye is berberine which is an alkaloid. It is a basic dye and can be used to dye silk and wool directly. The dye produces a bright yellow colour with good washing fastness and average light fastness. Cotton can be dyed after mordanting Pomegranate Rinds of pomegranate (Punica granatum) fruits are rich in tannins and are used for mordanting purposes. A yellow dye is also present which can be used to dye wool, silk, and cotton with good fastness properties.[7] It is also used along with turmeric for improving the light fastness of the dyed materials Brown and Black Dyes Oak galls are rich in tannin and are used for mordanting. They can also be used to get a brown colour. Catechu or cutch obtained from the heartwood of Acacia catechu is used to dye cotton, wool, and silk to brown colour 79 P a g e

7 directly. It is also rich in tannins and can be used to get black colour with iron mordant. Black colour can also be obtained from many yellow and red dyes by iron mordanting. Famous logwood black colour having very good fastness properties was obtained by using iron mordant and the extract of logwood obtained from the heartwood of the tree Haematoxylin campechianum found in Mexico and the West Indies. 3.2 Animal Origin Insects were the main source of natural dyes of animal origin and most of these provided red colours. The oldest animal origin dye, Tyrian purple, produced from the secretions of the sea mollusc Murex is an exception. This dye produced a very fast deep violet colour on fabrics. It was very expensive as thousands of molluscs were needed to get a gram of the dye. Hence it was considered a symbol of royalty and was used to colour the clothes of the royal family. Cochineal was an important animal origin dye obtained from the insects of the species called Dactylopius coccus which is still being used to dye textiles. The dye is obtained from the bodies of female insects that live on cactus (Opuntia species). The principal colouring matter is carminic acid. The cochineal dye produces crimson redcolour on animal fibres and has good washing and light fastness properties. Its bright red aluminium calcium chelate known as carmine is used as food colour. Kermes is another animal origin crimson red dye derived from the insect Kermes licis. This dye has been known since ancient times to colour animal fibres but was inferior to cochineal in fastness properties. Lac was also well known in ancient times for coloration of animal fibres. It is obtained from the hardened secretions (stick lac) of the insect Kerria lacca found on the twigs. 3.3 Mineral Origin Mineral pigments found in nature such as cinnabar, red ocher, yellow ocher, raw sienna, malachite, ultramarine blue, azurite, gypsum, talc, charcoal black, and so on, have been used for coloration purposes. 3.4 Microbial and Fungal Origin Bacteria produce collared substances as secondary metabolites. Bacillus, Brevibacterium, Flavobacterium, Achromobacter, Pseudomonas, Rhodococcus are some of the pigment-producing bacteria Microbes as a dye source offer an advantage as these can be easily grown on cheap substrates under controlled conditions. IV. EXTRACTION METHODS As natural dye-bearing materials contain only a small percentage of colouringmatter or dye along with a number of other plant and animal constituents such as water-insoluble fibers, carbohydrates, protein, chlorophyll, and tannins, among others, extraction is an essential step not only for preparing purified natural dyes but is also required to be carried out by users of crude dye-bearing materials.[8] As natural colouring materials are not a single chemical entity and the plant matrix also contains a variety of nondye plant constituents, extraction of natural dyes is a complex process. The nature and solubility characteristics of the colouring materials need to be ascertained before employing an extraction process. The different methods for extraction of colouring materials are: Aqueous extraction, Alkali or acid extraction, Microwave and ultrasonic assisted extraction, Fermentation, Enzymatic extraction, Solvent extraction and super critical fluid extraction. 80 P a g e

8 4.1 Advantages of Natural Dyes Minimal Environmental Impact Because they come from natural sources, natural dyes are not harmful to the environment, which makes it so appealing for consumers. [9] Natural dyes are biodegradable and disposing them does not cause pollution. Renewable Natural dyes are obtained from renewable sources that can be harnessed without imposing harm to the environment. Colour pay-off If you re going for a soft hue or soothing shade, natural dyes can help you achieve that look. Safe Some natural dyes, such as carmine found in lipsticks, will not cause harm or health problems when ingested. 4.2 Disadvantages of Natural Dyes Cost A larger amount of natural dyes may be needed in order to dye a specific amount of fabric as opposed to synthetic dyes. For instance, one pound of cotton may be dyed with just five grams of synthetic dye, whereas 230 grams of natural dye are needed to dye the same amount of material. Since that is the case, using natural dyes is more expensive than synthetic dyes. [10] Colour pay-off Colour pay-off from natural dyes tend to fade quickly. More so, quality may not be more consistent than what synthetic dyes can deliver. Availability Another issue with natural dyes is their availability. It can be difficult to produce because the availability of raw materials can vary from season to season, place, and species, whereas synthetic dyes can be produced in laboratories all year round. Harmful Effects Natural dyes can also be harmful to some extent. Logwood has ingredients, haematin and haematoxylin, that can have harmful effects when inhaled, ingested, or absorbed through the skin. Bloodroot, another natural dye source, can cause irritation and inflammation when inhaled. More so, natural dyes may need mordant for application. While these substances help the dye stick to fabrics, they can also be toxic. Sustainability While natural dye sources are renewable, sustainability can still be an issue for natural dyes because producing them require vast areas of land. V. CONCLUSION Recently a lot of concern and awareness towards maintenance of ecological balance has led to revival of natural colorants. Replacement of synthetic dyes by natural dyes should be made. Reconstruction of ancient and traditional dyeing technology should be made, it is essential that there should be intense work on natural dyes as well ason their dyeing behaviour and fastness properties, which will be helpful for their best practicalapplication. The natural dyes should be used by all the manufactures to make them eco-friendly. BIBLIOGRAPHY [1]. L Gularajan, Present Status Of Natural Dyes, Indian Journal of Fibre & Textile Research, Vol. 26, March-June 2001, pp [2]. M. Subramanian, Natural Dyes, a glimpse, Textile Asia, Vol 3,pp 32, Feb-mar, P a g e

9 [3]. S. Geetha Margret Soundri, Ecofriendly Antimicrobial Finishing of Textiles Using Natural Extract, Journal of International Academic Research For Multidisciplinary, 2014, Vol 2. [4]. Arup mukherjee, Sankar ray Maulik, Application of Natural dyes in Handloom sectors, Textile Trends, June 2005, pp. 38,39 [5]. R.Kanchana, Apurva Fernandes, Bhargavi Bhat, Saurabhi Budkule, Santeshwari Dessai and Reshma Mohan, Dyeing Of Textiles With Natural Dyes - An Eco-Friendly Approach, International Journal of Chem Tech Research CODEN( USA), Vol.5, No.5, pp , July-Sept 2013 [6]. S. Sumithra, Natural Dyeing and finishing of textile, emerging trends in Science and Management, ISBN , MTWU Publishers. [7]. V. A. Rinsey Antony, A Comparative Study on Enzymatic Degumming of Mulberry Silk and Natural Dyeing, Emerging trends in Science and Management, ISBN , MTWU Publishers. [8]. [9]. [10] P a g e