Dyeing of textiles with eco-friendly natural dyes: A review (original) (raw)

dyeing textiles with an Eco-friendly natural dyes

The use of natural dyes for textile dyeing purpose decreased to a large extent after the discovery of synthetic dyes in 1856. As a result with a distinct lowering in synthetic dyestuff costs, the natural dyes were virtually neglected at the beginning of twentieth century presently there is an excessive use of synthetic dyes estimated at around 10,000,000.00 tons per annum, the production and application of which releases large amount of wastes and unfixed colorants to the environment thereby causing serious health hazards and disturbing the eco-balance of nature. Due to the current economic and environmental consciousness, research in this front should be titled towards the use of natural dyes for dyeing textile materials. This article gives an in depth review and analysis on the categories of textile materials suitable for dyeing with natural dyes, equipments for home and small scale commercial natural dyeing of textile, extraction and mordents used in dyeing textile with natural dyes, conventional and non-conventional method of natural dyeing of textile as well as colour fastness properties of natural dyes. This could help in explaining the merits associated with the use of natural dyes other than synthetic dyes in textile dyeing to overcome the challenges of using synthetic dyes in textile dyeing and as well portray the benefits of using natural dyes

Dyeing Of Textiles With Natural Dyes - An Eco-Friendly Approach

Numerous plant species are found to have an important role in the day-to-day life of the ethnic and local people. However, it is a matter of concern that the indigenous knowledge of extraction, processing and practice of using of natural dyes has diminished to a great extent among the new generation of ethnic people due to easy availability of cheap synthetic dyes. Thus by keeping in view of above, the present study has been undertaken so as to revive the age-old are of dyeing with natural dyes. In the present work, the flowers of Clitoria ternatea (Clitoria flowers) and Targetes erecta Linn ( Marigold) and Punica granatum ( pomegranate) peel were used for the extraction of dye, dyeing of the selected fabrics at optimized conditions, using combination of mordants and evaluate the resultant colour fastness of the selected dyed samples to washing, rubbing, and light. Also the antimicrobial properties of the dyes were evaluated.

Dyeing of Textiles with Natural Dyes

intechopen.com

Textile materials (natural and synthetic) used to be coloured for value addition, look and desire of the customers. Anciently, this purpose of colouring textile was initiated using colours of natural source, untill synthetic colours/dyes were invented and commercialized. For ready availability of pure synthetic dyes of different types/classes and its cost advantages, most of textile dyers/ manufacturers shifted towards use of synthetic colourant. Almost all the synthetic colourants being synthesized from petrochemical sources through hazardous chemical processes poses threat towards its eco-friendliness. Hence, worldwide, growing consciousness about organic value of eco-friendly products has generated renewed interest of consumers towards use of textiles (preferably natural fibre product) dyed with eco-friendly natural dyes. Natural dyes are known for their use in colouring of food substrate, leather as well as natural fibres like wool, silk and cotton as major areas of application since prehistoric times. Although this ancient art of dyeing textiles with natural dyes withstood the ravages of time, but due to the wide availability of synthetic dyes at an economical price, a rapid decline in natural dyeing continued. However, even after a century, the uses of natural dyes never erode completely and they are being still used in different places of the world. Thus, natural dyeing of different textiles and leathers has been continued mainly in the decentralized sector for specialty products besides the use of synthetic dyes in the large scale sector for general textiles/apparels. Recently, most of the commercial dyers and textile export houses have started re-looking to the maximum possibilities of using natural dyes for dyeing and printing of different textiles for targeting niche market. Natural dyes produce very uncommon, soothing and soft shades as compared to synthetic dyes. On the other hand, synthetic dyes, which are widely available at an economical price and produce a wide variety of colours, sometimes causes skin allergy and other harmfulness to human body, produces toxicity/chemical hazards during its synthesis, releases undesirable/hazardous/toxic chemicals etc. For successful commercial use of natural dyes for any particular fibres, the appropriate and standardized techniques for dyeing for that particular fibre-natural dye system need to be adopted. Therefore to obtain newer shade with acceptable colour fastness behaviour and reproducible colour yield, appropriate scientific dyeing techniques/procedures are to be derived. Thus, relevant scientific studies and its output on standardization of dyeing www.intechopen.com Natural Dyes 30 methods, dyeing process variables, dyeing kinetics and test of compatibility of selective natural dyes have become very important, however the information on which is insufficient. That is why, this chapter is very much relevant to the current need of the textile dyers. An attempt has been made here to give scientific overview on dyeing of textiles with natural dyes and related issues. 2. Definition of natural dyes/colouants The word 'natural dye' covers all the dyes derived from the natural sources like plants, animal and minerals. Natural dyes are mostly non-substantive and must be applied on textiles by the help of mordants, usually a metallic salt, having an affinity for both the colouring matter and the fibre. Transition metal ions usually have strong coordinating power and/or capable of forming week to medium attraction/interaction forces and thus can act as bridging material to create substantivity of natural dyes/colourants when a textile material being impregnated with such metallic salt (i.e. mordanted) is subjected to dyeing with different natural dyes, usually having some mordantable groups facilitating fixation of such dye/colourant. These metallic mordants after combining with dye in the fibre, it forms an insoluble precipitate or lake and thus both the dye and mordant get fixed to become wash fast to a reasonable level. 3. Advantages and disadvantages of natural dyes/ colouants In the recent years, there has been a trend to revive the art of natural dyeing. This is mainly because in some aspects natural colourants are advantageous against synthetic dyes. Some of these advantages along with some limitations (disadvantages) are listed below: 3.1 Advantages of natural dyes/ colouants i. The shades produced by natural dyes/colourants are usually soft, lustrous and soothing to the human eye. ii. Natural dyestuff can produce a wide range of colours by mix and match system. A small variation in the dyeing technique or the use of different mordants with the same dye (polygenetic type natural dye) can shift the colours to a wide range or create totally new colours, which are not easily possible with synthetic dyestuffs. iii. Natural dyestuffs produce rare colour ideas and are automatically harmonizing. iv. Unlike non-renewable basic raw materials for synthetic dyes, the natural dyes are usually renewable, being agro-renewable/vegetable based and at the same time biodegradable. v. In some cases like harda, indigo etc., the waste in the process becomes an ideal fertilizer for use in agricultural fields. Therefore, no disposal problem of this natural waste. vi. Many plants thrive on wastelands. Thus, wasteland utilization is an added merit of the natural dyes. Dyes like madder grow as host in tea gardens. So there is no additional cost or effort required to grow it. vii. This is a labour intensive industry, thereby providing job opportunities for all those engaged in cultivation, extraction and application of these dyes on textile/food/leather etc. viii. Application of natural dyes has potential to earn carbon credit by reducing consumption of fossil fuel (petroleum) based synthetic dyes. www.intechopen.com Dyeing of Textiles with Natural Dyes 31 ix. Some of its constituents are anti-allergens, hence prove safe for skin contact and are mostly non-hazardous to human health. x. Some of the natural dyes are enhanced with age, while synthetic dyes fade with time. xi. Natural dyes bleed but do not stain other fabrics, turmeric being an exception. xii. Natural dyes are usually moth proof and can replace synthetic dyes in kids garments and foodstuffs for safety. Despite these advantages, natural dyes do carry some inherent disadvantages, which are responsible for the decline of this ancient art of dyeing textiles. 3.2 Limitation/ disadvantages of natural dyes/ colouants i. It is difficult to reproduce shades by using natural dyes/colourants, as these agroproducts vary from one crop season to another crop season, place to place and species to species, maturity period etc. ii. It is difficult to standardize a recipe for the use of natural dyes, as the natural dyeing process and its colour development depends not only on colour component but also on materials. iii. Natural dyeing requires skilled workmanship and is therefore expensive. Low colour yield of source natural dyes thus necessitates the use of more dyestuffs, larger dyeing time and excess cost for mordants and mordanting. iv. Scientific backup of a large part of the science involved in natural dyeing is still need to be explored. v. Lack of availability of precise technical knowledge on extraction and dyeing techniques. vi. The dyed textile may change colour when exposed to the sun, sweat and air. vii. Nearly all-natural dyes with a few exceptions require the use of mordants to fix them on to the textile substrate. While dyeing, a substantial portion of the mordant remains unexhausted in the residual dye bath and may pose serious effluent disposal problem. viii. With a few exceptions, most of the natural dyes are fugitive even when applied in conjunction with a mordant. Therefore, sometimes their colour fastness performance ratings are inadequate for modern textile usage.

Natural dyes with future aspects in dyeing of Textiles: A research article

Dyeing is a complex, specialized science. Nearly all dye stuffs are now producing from synthetic compounds. This means that costs have been greatly reduced and certain application and wear characteristics have been greatly enhanced. But many practitioners of the craft of natural dyeing (i.e. using naturally occurring sources of dye) maintain that natural dyes have a far superior aesthetic quality which is much more pleasing to the eye. On the other hand, many commercial practitioners feel the natural dyes are non-viable on grounds of both quality and economics. In the west, natural dyeing is now practiced only as a handcraft, synthetic dye being used in all commercial applications. Some craft, weavers and knitters use natural dye as a particular feature of their work.

Application of natural dyes on textiles

2009

This paper reports the studies available on the characterization and chemical/biochemical analysis of natural dyes; extraction of colorants from different natural sources; effects of different mordants and mordanting methods; conventional and non-conventional methods of natural dyeing; physico-chemical studies on dyeing process variables and dyeing kinetics; development of newer shades and analysis of colour parameters for textiles dyed with natural dyes; and test of compatibility for application of binary mixture of natural dyes. The chemical modification of textile substrate for improving dyeability, attempts for improvement in overall colour fastness properties and survey of some traditional processes of natural dyeing in different parts of India have also been discussed.

Textile dyeing by dyestuffs of natural origin

Hemijska industrija, 2006

The textile industry is one of the biggest industrial consumers of water especially dye houses which utilize synthetic dyes and other chemicals. Natural dyes are generally environmental friendly and have many advantages over synthetic dyes with respect to production and application. In recent years, there has been an interest in the application of these dyes due to their bio-degradability and higher compatibility with the environment. A review of previous work in the field of applying dyestuffs of natural source as possible textile dyes is given. From an ecological viewpoint, the substitution of chemical dyes by 'natural products' in textile dyeing may be feasible and may represent not only a strategy to reduce risks and pollutants, but also an opportunity for new markets and new businesses which can develop from the inclusion of ecology in trade policy.

A Review on Application of Natural Dyes on Textile Fabrics and Its Revival Strategy

Chemistry and Technology of Natural and Synthetic Dyes and Pigments [Working Title], 2020

A comprehensive review on application of natural dyes on textiles and earlier research findings has been discussed in this chapter. Moreover, recently the consumers have become very much conscious about the environment, renaissance of eco-friendly products and process like dyeing textiles with natural dyes, which has thus become also important now. Thus, revival of natural dye application on textiles and summary of earlier researches on standardization of its method of extraction, mordanting, dyeing process variables and even natural finishing, etc. have been elaborated in this review. Characterization of natural dyes and chemistry of its dyeing, etc. are equally important and hence are discussed here critically. Thus this part has become a unique readymade comprehensive chapter for information on chemistry and application of natural dyes on textiles and its revival strategy.

Review on Natural Dyes for Textiles from Wastes

Chemistry and Technology of Natural and Synthetic Dyes and Pigments, 2020

Agriculture and food processing industries generate a large amount of organic waste that still contains colouring pigments. Their sustainable use in dyeing textiles will expectedly solve the problem of their disposal. Some studies involving the use of agro and industrial waste have been documented in this chapter to provide a guideline for further research. Information on some selected wastes that have been used in dyeing of textiles by several authors have been listed, their composition and production details highlighted and their use is explained systematically. The documented studies have been placed in the form of case studies to highlight the different approaches of the authors for explaining the effectiveness of such wastes as a source for textile colourants. As reported in some studies, the extracted dye from the waste doubled up as a mordant itself. Most studies also indicate good dyeability with appreciable fastness with respect to the textiles dyed with such wastes. Some wastes have also reportedly rendered antibacterial and sun/light protective properties to the dyed fabric.