Dyeing studies with henna and madder: A research on effect of tin (II) chloride mordant

The present paper deals with the application of natural dyes extracted from powdered henna (Lawsonia inermis) leaves and madder (Rubia cordifolia) roots on woolen yarn and assessment of effect of stannous chloride mordant on dyeability, color characteristics, fastness properties and antifungal activity of dyed woolen yarn. Sixteen shades have been developed for the characterization of their color characteristics and fastness properties. The color strength (K/S value) has been found to be very good in all dyed woolen yarn samples. The color fastness with respect to light exposure, washing and rubbing was quite satisfactory for both henna as well as madder dyed samples. Henna leaves extract was found very effective against Candida glabrata both in solution as well as after application on wool substrate but no antifungal activity is reported in case of madder both in solution as well as on wool substrate

An eco-friendly dyeing of woolen yarn by Terminalia chebula extract with evaluations of kinetic and adsorption characteristics

In the present study Terminalia chebula was used as an eco-friendly natural colorant for sustainable textile coloration of woolen yarn with primary emphasis on thermodynamic and kinetic adsorption aspects of dyeing processes. Polyphenols and ellagitannins are the main coloring components of the dye extract. Assessment of the effect of pH on dye adsorption showed an increase in adsorption capacity with decreasing pH. Effect of temperature on dye adsorption showed 80 °C as optimum temperature for wool dyeing with T. chebula dye extract. Two kinetic equations, namely pseudo first-order and pseudo second-order equations, were employed to investigate the adsorption rates. Pseudo second-order model provided the best fit (R2 = 0.9908) to the experimental data. The equilibrium adsorption data were fitted by Freundlich and Langmuir isotherm models. The adsorption behavior accorded well (R2 = 0.9937) with Langmuir isotherm model. Variety of eco-friendly and sustainable shades were developed in combination with small amount of metallic mordants and assessed in terms of colorimetric (CIEL∗a∗b∗ and K/S) properties measured using spectrophotometer under D65 illuminant (10° standard observer). The fastness properties of dyed woolen yarn against light, washing, dry and wet rubbing were also evaluated

Dyeing studies and fastness properties of brown naphtoquinone colorant extracted from Juglans regia L on natural protein fiber using different metal salt mordants

In this study, wool fibers are dyed with a natural colorant extracted from walnut bark in presence and absence of mordants. The effect of aluminum sulfate, ferrous sulfate, and stannous chloride mordants on colorimetric and fastness properties of wool fibers was investigated. Juglone was identified as the main coloring component in walnut bark extract by UV visible and FTIR spectroscopic techniques. The results showed that pretreatment with metallic mordants substantially improved the colorimetric and fastness properties of wool fibers dyed with walnut bark extract. Ferrous sulfate and stannous chloride mordanted wool fibers shows best results than potassium aluminum sulfate mordanted and unmordanted wool fibers. This is ascribed due to strong chelating power of ferrous sulfate and stannous chloride mordants

Eco-friendly and effective dyeing of wool with anthraquinone colorants extracted from Rubia cordifolia roots: Optimization, colorimetric and fastness assay

The present study is aimed to explore the dyeing ability of anthraquinone colorants extracted from Rubia cordifolia Lin. roots. Sustainable approach for textile dyeing with a systematic protocol is followed with the effect of AlCl3 and CaCl2 metallic mordants. The optimization of extraction and dyeing conditions was assessed by Reflectance Spectrophotometry. The optimum extraction and dyeing conditions were found to be pH = 2, time = 45 min and temperature 90 °C and pH = 4, time = 90 min and temperature 90 °C respectively. At optimized conditions, dyeing abilities of pre-mordanted with metallic salts as anchoring agent (AlCl3 and CaCl2) were compared. Wool samples dyed with Madder root extract impart radiant red shades with or without mordants having different hue and tones with commercially acceptable colorimetric and fastness properties without sacrificing much of the resources. Effective improvement in color as well as fastness properties was observed using anchoring agents

Plant phenolics: a review on modern extraction techniques

Interest in the development of procedures for extraction of bioactive compounds from natural sources has increased in recent years due to the potential applications of these compounds in food, chemical and pharmaceutical industries. The retrieval of phenolics from plant materials is greatly influenced by the extraction procedure employed and related factors. This chapter provides an updated overview of the methods used to extract phenolic compounds from plant sources, ranging from more traditional to advanced extraction processes. Problems associated with conventional extraction procedures led to demand for alternative techniques for extraction of phenolic compounds and several new extraction techniques have been developed and refined in last two decades because of their potential to efficiently extract a great variety of valuable phenolic compounds. Some promising extraction protocols used to extract the different type of plant phenolics are discussed in detail

Recent advancements in natural dye applications: a review

A vast array of colorants obtained from natural sources such as plants, insects/animals and microbes have been scrutinized in recent past for their use in different kinds of applications. Research into new natural dyes sources along with eco-friendly, robust and cost-effective technologies for their processing and application have greatly aided in widening the scope of natural dyes in various traditional and advanced application disciplines. This review encompasses a summary of research performed in last 15 years (1998–2013) in different arenas of applications of natural dyes, with specific reference to technological development in natural textile dyeing and use of natural dyes in functional finishing of textiles, food coloration and dye-sensitized solar cells. In addition, some newly discovered applications of natural dyes have also been discussed

Green chemistry approaches to develop antimicrobial textiles based on sustainable biopolymers—a review

In recent years, the population explosion and environmental pollution have increased the interest of researchers in the discovery of new health and hygiene-related products for the well being of mankind. Among the possible approaches initiated by the textile industry, the use of low-environmental impact technologies- based on sustainable biopolymers- presents a novel possible avenue for large scale development of bioactive textiles. The purpose of this article is to review the information on the role of different biopolymers in the development of antimicrobial textiles. Increased sustainability, environment friendliness, reduced pollution, green chemistry, renewability and intrinsic biological activity are some of the attributes which make chitosan, cyclodextrin, sericin protein, and alginate suitable alternative agents for the functional finishing of textile materials. The application of biopolymers, along with the recent impact of various “green chemistry” strategies, on the antimicrobial properties of textile fibers is reviewed. It also includes a brief review on different green pretreatment technologies used for the surface modification of textiles with a special reference to their influence on antimicrobial properties. Finally, the advantages and future studies regarding the use of nanotechnology in the antimicrobial finishing of textiles is also outlined

Perspectives for natural product based agents derived from industrial plants in textile applications – a review

With the consumer's enhanced awareness of eco-safety, there has been an increasing tendency towards the use of sustainable and environmentally friendly materials. In recent years, considerable attention has been given to the products produced from non-food crops for use in various industries notably in the textile industry. Based on biocompatibility, biodegradability, non-toxicity, in addition to their recently discovered properties such as insect repellent, deodorizing, flame retardant, UV protection, and antimicrobial activity are gaining popularity all around the world for producing more appealing and highly functional value-added textiles. This review article highlights the most important textile applications of environmental friendly plant-based products such as fibres, polysaccharides, dyes and pigments, polyphenols, oils and other biologically active compounds. This is followed by a focus on plant derived bioactive agents with antimicrobial properties and application of these agents to the textiles. Apart from this, the contribution of plant-based agents to green nanotechnology in recent years for the development of bioactive textiles is also outlined

Colourful and Functional Silk Fabric Via Caffeic Acid Assisted in Situ Generation of Silver Nanoparticles

A successful approach for the in situ silver nanoparticles (AgNPs) generation by caffeic assisted reduction of a silver salt on silk fabric is reported herein. The formation of AgNPs in solution was monitored by UV-vis spectrophotometer. The morphological structure of AgNPs formed on silk fabric was observed by scanning electron microscopy studies. Inductively coupled plasma technique was used to determine the silver content of the treated fabric. An increase in the amount of caffeic acid and silver nitrate resulted in more silver being deposited on silk fabric. The measurements of the colour characteristics, UV-protection ability, and antibacterial properties of the treated fabrics revealed that the caffeic acid assisted in situ generation of AgNPs imparted good multi-functional properties and displayed golden yellow color to the treated fabrics