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Abstract: An ecological approach has been presented by valorisation of outer green shell of almond fruit as a novel natural dye using chemical solvent free extraction, small amount of metallic mordant, alternative natural mordants, auxiliary free dyeing and washing. The main objective of this study is to evaluate biomordants versus metal mordants and to reveal the substitution of the prevalent metallic mordants for biomordants as renewable natural sources. The use of a smaller amount of metallic mordant (0.2 g/L - 1 %) and less plant (1 g plant/3 g fabric) than in most current natural dye applications is a major advantage of dyeing with almond shell extract. Wool fabrics dyed using metallic mordants namely alum, iron II sulfate, copper II sulfate and potassium dichromate were compared with the samples dyed using biomordants; powder of valex (acorn of Quercus ithaburensis ssp. macrolepis), pomegranate (Punica granatum L.) rind, rosemary (Rosmarinus officinalis) and thuja (Thuja orientalis) leaves in terms of colour measurements, light and wash fastness values. These biomordants were used alone and in conjunction with almond shell extract in the same bath to dye wool fabric. Rose, brown, cinnamon and burgundy/reddish hues were achieved by using alum, iron II sulfate, copper II sulfate and potassium dichromate respectively. Especially rose and burgundy/reddish shades are unique colours for natural dyes. Biomordants exhibited different interactions with almond shell extract resulting in quite different colour gamuts. Rosemary can be alternative to alum (pre and post mordanting), iron II sulfate (pre mordanting) and copper II sulfate (pre, simultaneous and post mordanting). Thuja orientalis leaves, valex and pomegranate rind cannot be precisely substituted for any of the metallic mordants used in this research. However, thuja leaves with almond shell ensured relatively similar colours to alum (pre and post mordanting). Considering the fastness properties; thuja was not effective on washing and light fastness, valex and pomegranate rind improved both washing and light fastness, rosemary was not effective on light fastness while it slightly improved the washing fastness. Valex and pomegranate produced equal light fastness to copper and iron mordant while they exceeded that of the alum and chromium. The light fastness values of rosemary and thuja were similar to alum and chromium and less than copper and iron. Use of biomordants is very promising concept as an alternative method that may help to reduce the reliance on toxic metal salt mordants. [Copyright &y& Elsevier]

Abstract: In this research, extraction of dyes from Opuntia ficus-indica was conferred by ultrasound. Dyes extracted and isolated from Opuntia ficus-indica plant were separated by fractional crystallization method and characterized by mass techniques. The dyeing of wool fabric using betanin as natural dye and Chlorophyll-a as biomordant has been studied. Results show an increase in the colour strength values with increasing the concentration of biomordant. The effect of treatment variables on the colour strength of dyed fibres was also examined. It was found that pH and temperature of dyeing influences considerably the results; this is mainly linked to the stability conditions of betanin dye. Dye exhaustion was studied in both conventional and ultrasonic dyeing process. It was shown that sonication improve dye exhaustion from rating 30% to rating 60% in a shorter dyeing time. The fastness properties of dyed wool against washing, light, dry and wet rubbing were evaluated. Un-mordanted and mordanted samples have good fastness properties. [Copyright &y& Elsevier]

Rubia cordifolia (Tamin, local name) produces anthraquinone reddish orange dyes in roots, stem and leaves, which has been used for dyeing textiles since ancient times. Commercial sonicator dyeing with Rubia showed that pretreatment with biomordant, Eurya acuminata DC var euprista Karth. (Theaceae family) [local name, Nausankhee (Apatani tribe), Turku (Nyishi tribe) in 2%] shows very good fastness properties for dyed cotton using dry powder as 10% of the weight of the fabric is optimum. Use of biomordant replaces metal mordants making natural dyeing ecofriendly. [Copyright &y& Elsevier]

• An effective and value-adding management of agricultural waste of fruit seeds. • Replacing toxic metal mordants with environmental friendly bio mordants. • Achieving a variety of color shades with enhanced color strength and fastness. • Achieving fabric bio-functions of UV protection, antioxidant and antibacterial properties. As agricultural waste, fruit seeds have received little attention in producing natural colorant for textile dyeing application. This work uses Eriobotrya japonica L. seed skins (EJSS) as source of natural dye for the coloration and bio-functional finishing of wool fabric. Investigation has been made to the optimal extracting conditions (such as solvent system, pH, temperature and time) and natural dye characterization (chemical components, surface morphology, and thermal stability) using UV–vis, Fourier-transform infrared spectroscopy (FT-IR), Scanning electron microscope (SEM), thermogravimetric analysis (TGA), Energy Dispersive X-rays Spectroscopy (EDS) and Differential calorimetry (DSC). Flora leaves of Chinese Tallow, Folium Artemisiae Argyi and Cinnamomum Camphora were used to produce bio-mordants in this work. Pre-mordant fabric dyeing was conducted with comparisons made between bio-mordants and traditional metal ion mordants (ferrous sulfate, potassium aluminium sulfate, and copper sulfate). Results showed that pre-mordant dyeing using EJSS natural dye can produce wool fabric with a variety of shades with enhanced color strength, color fastness, and bio-functions (such as UV protection, antioxidant and antibacterial properties). Fabric mordanted with tannin-rich bio-mordant showed the best color strength and excellent functional behavior due to the high interaction between fiber and dye molecules activated by functional groups (such as phenolic groups). The outcome of this study can provide a potential to the application of agricultural waste to the natural dyeing of textile, as well as to a value-adding green waste management. [ABSTRACT FROM AUTHOR]