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This paper aims to extract the dye colourant from teak leaves using different aqueous mediums (Alkaline, Neutral and Acidic); to characterize the dye in terms of yield %; ash content and moisture content; to standardize the conditions of application of dye extracted from teak leaves on selected natural and synthetic fabrics using selected natural and chemical mordants; to assess the colour value (K/S, L*, c*/ h*, a*, b*) and fastness properties of the dyed samples in terms of wash, rub, light and perspiration fastness; and to develop dyed and printed designs using combinations of mordant and extracted dye.

Stage 1 – Extraction of dye from teak leaves; and characterization of dye: yield% ash content and moisture content. Stage 2 – Preparation of fabrics for dyeing; optimization of mordanting parameters using pre mordanting method followed by post mordanting; and optimization of dyeing parameters. Stage 3 – Testing of dyed fabric – Colour Measurement; K/S L*a*b*/L*c*h*; fastness properties; wash fastness done in the Laundrometer using ISO 2 standard test method; crock fastness done by Crockmeter using AATCC 116–1995 test method; perspiration fastness tested by perspirometer using AATCC 15– 2007 test method; and light fastness assessment in Mercury Bulb Tungsten Filament (MBTF) light fastness tester using AATCC Test Method 16–2004.

The findings of the study show that waste teak leaves can be used as an effective dye for natural as well as synthetic fabrics giving a wide range of colours on wool, silk and nylon. The maximum relative colour strength of the extracted dye on unmordanted dyed samples was found to be at pH 5 on wool and silk and at pH 7 on nylon. A range of shades was obtained with the use of different mordants. The extracted dye showed moderate to good fastness properties in terms of light, wash, rub and perspiration on wool and silk and excellent on nylon. Fastness properties were found to improve with the application of mordants both as pre and post method. Various combinations of mordants and dye result in obtaining pleasing and harmonious colours which were used aesthetically for printing.

Due to time constrains, extraction in an organic medium could not be done, which could be a further scope for study.

Dyeing using teak leaves is a step towards sustainability and effective waste utilization with promising potential for application on natural as well as synthetic fabrics. Good colour with added properties will provide excellent solutions for eco-friendly methods of dyeing.

This paper demonstrates the new possibilities offered by innovative uses of by-products of the timber industry and open good prospects for alternatives to synthetic colourants and new markets for the textile industry. It offers a new tool for the development of slow fashion.

It is a common practice to prune the tree branches to improve wood quality; thus, leaves are easily available as by product from pruning and also from wood harvesting. In the present study, waste teak leaves (Tectona grandis L.) were used for the extraction of dye.

Sulphur dyes are the most highly consumed colourants for cellulosic substrates owing to their reasonable cost and acceptable fastness. However, the use of noxious conventional reducing agent, sodium sulphide and impaired wash fastness against oxidative bleaching is gradually decreasing the market of these dyes. As the need for “Green” goods and services is raising public awareness, this paper aims to use a glucose-based biodegradable reducing agent in place of sodium sulphide to dye cotton fabrics with a range of commercial sulphur dyes. The study also proposes an aftertreatment method to improve the fastness properties of the dyeing.

The paper investigated the impact of a newly developed aftertreatment method on the fastness properties of dyeing. This involved the sequential application of a cationic fixing agent (Tinofix ECO) and tannin (Bayprotect CL) on the coloured fabrics and subsequent evaluation of colour strength, washing, light and rubbing fastness.

The effect of aftertreating the dyed cotton was found to significantly improve the light and wet rub fastness. The surface morphology of the dyeing remained unaffected as depicted by the absence of any finish residues.

The protective effect of the cation–tannin aftertreatments was examined with a view to providing the necessary commercial performance; however, it was established that the dry rub fastness was either reduced or remained unaffected and the wash fastness to International Organization for Standardization 105 C09 was also marginal.

This finishing technique is novel and can be found useful for manufacturing sulphur-dyed products with the improved light and wet rub fastness.

The purpose of this study is to investigate the possibility of dyeing polyester (PET) fabric with natural dye extracted from annatto seeds using high temperature dyeing method.

PET fabric was dyed with annatto extract by varying dyeing parameters (temperature, time, pH and dye concentration) to determine the optimum dyeing conditions. The influences of KAl(SO₄)₂, FeSO₄, gallnut mordants or a commercial UV absorber on colour yield and fastness properties were further studied.

Optimum results were obtained when the fabric was dyed at 130°C for 30 min in a dyebath containing 15 per cent (owf) annatto dye at pH 6. The dyed fabric had an orange shade and exhibited good to excellent wash, crock, perspiration fastness and fair light fastness. Further dyeing with mordants or UV absorber mostly resulted in lower colour yield and similar fastness properties.

Although the light fastness was slightly improved to moderate level for the sample with UV absorber, a noticeable colour staining on cotton portion of multi-fibre fabric occurred when subjected to standard washing test. Compared to C.I. Disperse Orange 73, the annatto dye exhibited comparable colour fastness but had inferior light fastness when dyed at approximately the same colour strength.

Natural colourants from annatto seeds can be used to dye PET fabric at high temperature without mordants, yielding deep orange shade and satisfactory fastness properties. This study provides a promising application to reduce the environmental impact of synthetic dyes.

The present study aims to focus on the feasibility of using an aqueous extract from the fruit shell of Camellia oleifera Abel as a source of natural colourant in printing-paste preparation for pigment printing of cotton fabric. The effects of pre- and post-mordanting with three common metallic mordants, that is AlK(SO₄)₂, CuSO₄ and FeSO₄ on colour yield and colour fastness properties are also investigated.

The printing paste was prepared by mixing the concentrated Camellia oleifera Abel fruit shell extract solution with commercially available synthetic thickener and binder. The fabric sample was printed with the prepared printing paste using a flat-screen printing technique. To determine the effects of pre- and post-mordanting, AlK(SO₄)₂, CuSO₄ and FeSO₄ mordant aqueous solutions with various concentrations were applied using the pad-dry technique. Comparisons between printing with and without mordants were evaluated in terms of colour strength (K/S values) and colour fastness to washing, light, crocking and perspiration.

Without the mordants, the printed fabric had a yellowish brown shade with acceptable colour fastness properties, that is fair to good wash fastness, moderate light fastness, good to very good crocking fastness and fair to good perspiration fastness. The use of mordants, especially CuSO₄ and FeSO₄, not only enhanced colour strength but also imparted different colours to the fabric. Compared to the unmordanted fabrics, colour fastness properties were mostly comparable or improved in the mordanted fabrics depending on the type and concentration of mordants.

Although in the case of CuSO₄ the light fastness was increased to a good to very good level, it is recommended that the final print be produced with a concentration of less than 0.125 gL⁻¹ to yield the print with the residual amount of Cu metal under the limit, that is less than 50 ppm as regulated by the Oeko-Tex^® standard.

The obtained prints from Camellia oleifera Abel fruit shell extract provided shades with satisfactory colour fastness to washing, light, crocking and perspiration. The extract from Camellia oleifera Abel fruit shell has the potential to be used as an alternative to synthetic dye in the textile industry.

The use of Camellia oleifera Abel fruit shells, which are considered as abundant byproducts of tea seed oil production, as natural colouring agents for pigment printing of cotton fabric has been reported for the first time. It will minimise the environmental impact of this waste and create more valuable textile products.

The purpose of this paper is to extract the eco-friendly natural dye obtained from the flower of Spathodea campanulata and apply on silk fabric using combination of mordants. The fastness properties of the flower of Spathodea campanulata dyed silk fabric have been studied using different combination (1:3, 1:1 and 3:1) of various mordants, such as myrobolan: nickel sulphate, myrobolan: aluminium sulphate, myrobolan: potassium dichromate, myrobolan: ferrous sulphate and myrobolan: stannous chloride. The wash, rub, light and perspiration fastness of the dyed samples have been evaluated.

For dyeing there are three methods are used. They are Pre mordanting, Simultaneous mordanting and Post mordanting methods. Dyed silk materials are tested by using wash fastness, rub fastness, light and perspiration fastness methods.

It is found that Spathodea campanulata dye can be successfully used for the dyeing of silk to obtain a wide range colours by using various combinations of mordants. With regards to colour fastness, test samples exhibit excellent fastness to washing, rubbing, except for pre-mordanting using myrobolan: potassium dichromate combination; and good to excellent fastness to perspiration in both acidic and alkaline media.

Availability of literature related to this work is not available. The study of combination of mordants of this natural dye on silk is a new research work and the large scale preparation is definitely very useful to the society.

The study aims to synthesise new thiophene-based dyes by an efficient method using sodium a-cyanoketene dithiolates as starting components for synthesis of tetra-substituted thiophenes, which act as a coupler for the synthesised dye. The synthesised dyes are applied for printing polyamide and polyester fabrics using the screen printing technique.

Treatment of 1 with carbon disulfide in alkaline medium forming disodium salt 2, which act as starting point for heterocyclisation to prepare these dye stuff 7. Sodium a-cyanoketene dithiolates 2 react with two moles of phenacyl bromide derivatives, forming alkylsulfanylthiophenes which react with the diazonium salt, forming the target dyestuff. These prepared dyes are used to print polyamide and polyester fabrics by using a synthetic thickener in the printing paste using screen-printing techniques.

The structure of synthesised dyes were established and confirmed for the reaction products on the basis of their elemental analysis and spectral data (IR and 1H-NMR). The suitability of the prepared dyestuffs for screen printing on polyamide and polyester fabrics has been investigated. The prints obtained from dyes possess high colour strength as well as excellent overall fastness properties.

The diazo coupling reaction of the starting tetra-substituted thiophene 5 with diazotised aromatic amines resulted in the formation of the corresponding dye. The synthesised dyes were utilised in preparing a paste for polyester and polyamide fabric printing. In addition, both of the variations of the substituents on the synthesised dyes and the fastness properties were also studied.

The synthesised dyes are superior in terms of yield, purity, colour strength and fastness properties, which lead to valuable achievements for commercial production.

The synthesised dyes are superior for application in fabrics.

The synthesis for novel thiophene-based dye stuff for application in printing properties on polyester and polyamide fabrics and study their fastness properties.

Sulphur dyes provide an inexpensive medium to dye cellulosic fibres with heavy shade depths. They offer moderate to good fastness to light and wet treatments. However, owing to the environmental hazard produced by the use of sodium sulphide, the practical implication of these dyes is steadily decreasing. Moreover, these dyes are prone to oxidation causing pronounced fading on exposure to laundering. This paper aims to present the green processing of sulphur dyes by using a biodegradable reducing agent in place of sodium sulphide to dye cotton fabrics. The study also proposes after-treatments with tannin to improve the fastness properties of the dyeings.

In this study, dyeings were produced on cotton fabric with a range of C.I. Leuco Sulphur dyes, which were reduced with sodium sulphide and glucose. Sulphur dyeings were after-treated with an environment-friendly tannin-based product (Bayprotect CL (BP)); subsequently, the after-treated samples were evaluated for colour strength, wash, light and rubbing fastness.

A novel after-treatment method was developed, which substantially improved the wash fastness of C.I. Leuco Sulphur Black 1 dyeing to ISO 105 C06/C09 washing. However, the degree of this improvement varied for the other sulphur dyes used. The surface morphology and the possible mechanisms for the improved fastness properties were also discussed.

The effect of after-treatment was significant for improving the wash fastness of sulphur black dyeings in particular, while the effect on other colours was minor. Significant improvements were observed for light and wet rub fastness for most of the dyeings, which signifies the importance of tannins as a finishing agent.

It is observed that the tannin-based product, BP, is found to provide the photoprotective effect by improving the lightfastness of the dyeings. Future research may involve the exploration of various tannins as a finishing agent to sulphur dyeings.

This novel finishing technique is found significant for improving the wash fastness of sulphur black 1 dyeings for both the reducing systems. Improvements were also observed for light and wet rub fastnesses for most of the dyeings.

This study aims to the synthesis of some novel 4-arylazo-3-hydroxythiophene analogues containing sulphapyridine and sulphathiazole dyestuffs and studying their application in dyeing polyester fabrics and rendering their antibacterial efficacy.

Simultaneous dyeing and antibacterial finishing for polyester fabric using a new antibacterial disperse dye having a modified chemical structure to thiophene dyes were studied. Construction of the thiophene dyes was carried out by diazo-coupling of diazotized sulphonamide-containing heterocyclic rings sulphapyridine and sulphathiazole with ethyl α-phenylthiocarbamoyl-acetoacetate followed by cyclizing the produced 2-arylazo-thioacetanilide with various α-halogenated reagents. All newly synthesized compounds were characterized by elemental analysis and extensive study of their spectral data (IR and ¹H-NMR). The dyeing characteristics of these thiophene dyestuffs were evaluated at optimum conditions. Antibacterial activities of the obtained thiophene dyes were studied against some Gram-positive and Gram-negative bacteria.

The synthesized thiophene-containing sulphonamides dyes were applied on polyester fabric. The modified dyes exhibited a good fastness properties and antibacterial efficacy against some Gram-positive and Gram-negative bacteria. Synthesized dyes showed higher antibacterial potency than the reference standard drug.

Synthesis of these disperse azo dyes for textile dyeing had never been reported previously.

The dyestuffs derived from thiophene are reasonable azo disperse dyestuffs giving good all-round fastness properties on polyester fabrics.

Thiophene dyes are used for dyeing polyester fabrics with brilliant colour and good fastness properties. The presence of sulphonamides moieties increase their fastness properties and elevate their antibacterial properties. Moreover, they can be used as antimicrobial finish due to their bactericidal properties on dyed textiles. This work afforded a new thiophene colorant that can be used in many different uses like polyester packing, thread Surgery, blends and other uses in medical textile.

The application of indigo dyes in the denim industries has been criticised due to the introduction of non-renewable oxidation products into the environment. Previous studies have investigated that reducing sugars can be used as green alternatives to sodium dithionite in the indigo dyeing of cotton fabric owing to their reduced and stable redox potential in the dye bath. The purpose of this study was to dye denim cotton fabric with indigo dye using various reducing sugars and alkalis. The use of sucrose and potassium hydroxide (KOH) for indigo dyeing has been explored for the first time.

A mixed factorial design with four variables including alkali, pH, number of dips and type of reducing sugar at different levels was studied to identify a significant correlation between the effect of these variables on the colour strength and fastness properties of the dyeings.

Investigations were made to examine the significant factors and interactions of the selected responses in the eco-friendly dyeing method. This process has the potential to reduce the load of sulphite and sulphate generated in the dyebath due to the use of a conventional reducing agent, sodium dithionite. The colour strength of the dyeing reduced with fructose was found to be better than other reducing sugars and significantly influenced by the number of dips, pH levels and the interaction between pH and reducing sugars. Using fructose for indigo dyeing with two dips at a pH of 11.5, using KOH as an alkali, results in higher colour strength values. The fastness properties of the indigo-dyed sample with reducing sugars ranging from fair to good or good to excellent. Specifically, colour change receives a rating of grey scale 3–4, staining 4–5, dry rubbing 4 and light fastness 3–4. These assessments hold true across various factors such as the type of reducing sugar, alkali, pH and the number of dips. The optimised parameters leading to improved colour strength and fastness properties are also discussed.

This dyeing technique is novel and a green alternative to dithionite denim dyeing. This process is found to be useful for indigo dyeing of denim fabric leading to reduced and stable redox potential in the dyebath and acceptable colour strength of the dyed fabric.

This paper aims to synthesize some new heterocyclic disperse azo dyes and their application in dyeing of polyester and polyamide fabrics.

Pyrazolopyrimidine derivatives containing arylazo function by the reaction of 3,5‐ diaminopyrazole with ketene dithioacetals were prepared. The prepared dyestuffs are established using elemental analysis, IR measurements, ¹H‐NMR and Mass spectra.

2,5‐diamino‐3‐arylazo‐N‐aryl‐6‐carboxamide‐7‐methylthio‐pyrazolo[1,5‐a]pyrimidine have been synthesized by the simple method. The dyed fabrics have a very good (4‐5) to excellent (5) results toward washing, perspiration, and rubbing fastness properties. The dyes are superior in terms of preparation and fastness properties.

The disperse azo dyes used in this paper were synthesized via a step‐wise pathway leading to the new azo dyes. In addition, the variations in substituents and sites of location on the heterocyclic moiety could also be studied.

The new azo dye systems based on substituted pyrazolopyrimidine provided a series of azo dyes with improved dyeing properties. The dyes are superior in terms of yield, purity, colour strength, and fastness properties and will lead to valuable achievements for commercial production.

The synthesized disperse azo dyes are superior in terms of preparation, yield, purity, and fastness properties.