Search Results (96)

Recently, the natural dyeing process has achieved great importance in the textile wet processing industry due to its clean dyeing, eco-friendliness, and nontoxicity in nature. In the above research project, a unique natural dye extracted from dragon fruit was applied to wool fabric using various mordanting agents to encourage the use of natural dyes and lessen the negative environmental effects caused by synthetic dyeing. The color characteristics (K/S), fastness properties, Fourier transform infrared spectroscopy (FTIR), absorption spectra, and thermal and ultraviolet (UV) resistance of the extracted dye and dyed wool samples were tested and characterized. The K/S values of the dyed wool fabrics were between 5.75 and 13.29. The color fastness ratings obtained from the dyed wool fabric were found to be between good and excellent. Hence, the overall results proved that the novel natural dye obtained from dragon fruit can be utilized for dyeing wool material for the production of eco-friendly and sustainable antimicrobial textiles. Full article

Early modern materials are not well represented in dye and mordant analyses despite extensive documentary evidence suggesting the enormous demand for coloured fabrics, even among those below the elite. Non-wovens likewise receive less attention than woven textiles despite their ubiquity in the early modern historical record. Knitted garments, in particular, have rarely been subjected to dye analysis. One garment is noteworthy for its colourfulness, despite not being visible in formal wear. Men throughout society wore knitted undergarments known as waistcoats from the late sixteenth century. The waistcoats under investigation here are from the collections at the London Museum and the Grimsthorpe and Drummond Castle Trust, Scotland. They are made of silk and are now a pale blue-green colour. Small samples were taken from each and subjected to a series of analytical techniques: micro-Raman spectroscopy, UV-Vis microspectrofluorimetry, and high-performance liquid chromatography (HPLC) coupled with a mass spectrometer. Using this protocol, it was possible to characterise the dyes in the waistcoats by ensuring that maximum information was gleaned from a sample before it was exhausted. Full article

The growing activity in the textile industry has been demanding the search for new and innovative technologies to meet consumers’ needs regarding more sustainable and ecological processes, with functionality receiving more attention. Bee products are known for their wide spectra of properties, including antioxidant and antibacterial activities. Propolis and honey are the most popular and used since ancient times for the most diverse applications due to their health benefits. With the increasing need for safer and more sustainable practices, the use of natural products for the functional finishing process can be a suitable alternative due to their safety and eco-friendly nature. For that, a biosolution, composed of a mixture of propolis and honey in water, was used to perform the functional finishing of cotton knits, both in the presence and in the absence of potassium alum as a chemical mordant. The fastness strength was also evaluated after three washing cycles. The antioxidant potential of the biosolution, assessed with the in vitro ABTS scavenging assay, provided textiles with the capacity to reduce more than 90% of the ABTS radical, regardless of the mordant presence and even after three washing cycles. Furthermore, biofunctional textiles decreased the growth of Bacillus subtilis, Propionibacterium acnes, Escherichia coli, and, particularly, Staphylococcus aureus cultures after 24 h of incubation with an increase in antibacterial activity when potassium alum was used. These findings show that bee products are promising and effective alternatives to be used in the textile industry to confer antioxidant and antibacterial properties to cotton textiles, thereby enhancing human health. Full article

This study investigates the practices and rules of Genoese gilding, drawing insights from a 16th-century manuscript containing regulations for gold leaf production. Employing X-ray and ion beam techniques, we quantitatively assess the manuscript’s gold leaf thickness without destructive sampling. Artisanal goldbeater-produced leaves of different thicknesses, applied with a guazzo or mordant technique, served as standards. Further analysis of samples with unknown thickness from the furniture of Palazzo Spinola di Pellicceria in Genoa (Italy) has confirmed the method’s applicability to practical cases. External beam Rutherford backscattering spectrometry (RBS) and particle-induced X-ray emission (PIXE) analyses were carried out using 3 MeV protons at the LABEC accelerator laboratory in Florence. A linear relationship between Gold Lα peak yield and leaf thickness, as measured by RBS, has been established for optimal calibration of portable or hand-held X-Ray fluorescence (XRF) instrumentation for in situ measurements. Moreover, the caratage of the gold foil preserved in the manuscript has been assessed. Full article

To protect skin from harmful ultraviolet (UV) radiation, there has been a resurgence in the use of natural dyes with metal mordants to reduce contamination by advanced chemicals. This study achieved natural dyeing in violet and yellow colors from Gromwell red roots and Cape jasmine seeds for UV-protective materials. The dyed fabrics were subjected to zinc oxide (ZnO) and polyphenol treatments, as well as copper post-mordanting. The SEM, TEM, and XRD tests showed that the ZnO nanoparticles, with hexagonal crystal structures, stuck to the fiber surfaces, and twisted strands resulted in the K/S reduction. First, this study found that the untreated cotton in violet, despite the highest K/S, faded the most intensely when exposed to UV. The color variation of untreated polyester was narrow, with little change in L, a*, and K/S. The color change of yellow-dyed samples treated with ZnO/polyphenol was not considerable in yellowness (b*: 28.838), while the violet fabrics displayed a significant decrease in K/S and an increase in b*. The combination of ZnO and polyphenol treatment improved UV absorption at 350 to 250 nm. Among the Cu-mordanted fabrics after ZnO/phenols treatment, the violet cotton turned reddish from blueish (negative to positive b*), with a hue change of 316° to 59° and the highest ΔE (25.90 ± 4.34) after UV exposure. In this study, the combination of ZnO/polyphenol with Cu-mordants allowed the Cape jasmine-dyed polyester to achieve a minimum ΔE as well as to keep its chroma and hue after UV exposure. Full article

Most traditional synthetic dyes and functional reagents used in silk fabrics are not biodegradable and lack green environmental protection. Natural dyes have attracted more and more attention because of their coloring, functionalization effects, and environmental benefits. In this study, natural dyes were extracted from lac and used for coloring and functionalization in silk fabrics without any other harmful dyes. The extraction conditions were studied and analyzed by the univariate method. The optimal extraction process was that the volume ratio of ethanol to water was 60:40 with a solid–liquid ratio of 1:10, and reacting under the neutrality condition for 1 h at 70 °C. Silk fabric can be dyed dark owing to the certain lifting property of lac. After being dyed by Al³⁺ post-medium, the levels of the washing fastness, light fastness, and friction fastness of silk fabric are all above four with excellent fastness. The results show that the dyed silk fabrics have good UV protection, antioxidation, and antibacterial properties. The UV protection coefficient UPF is 42.68, the antioxidant property is 98.57%, and the antibacterial property can reach more than 80%. Therefore, the dyeing and functionalization of silk fabrics by utilizing naturally lac dyes show broad prospects in terms of the application of green sustainable dyeing and functionalization. Full article

This paper presents a historical analysis of a rare dyer’s manuscript, preserved within the Museum of Industry in Ghent, Belgium. The manuscript, originating from a dyer in late 18th-century Antwerp, includes an extensive collection of recipes. The study will enable researchers to better grasp the practices of traditional dyeing techniques and materials in the region during that time. The manuscript focuses primarily on the dyeing of woolen fabrics. Approximately 90 of the 132 recipes utilize red dyes. Recipes for dying orange, brown, black, blue, and green colors are also described. The document mentions the use of madder, brazilwood, redwood, and cochineal. To create a variety of red shades, the dyer describes how fabrics were treated with different mordanting compounds, with alum and tin as the main ingredients, and how the dyeing solutions were prepared. The resulting colors include ‘madder red’, ‘formal red’, ‘crimson’, ‘scarlet’, ‘Turkish red’, ‘fire color’ and ‘flesh color’. In addition to the dyeing recipes, the manuscript contains various accounting documents and correspondences between the dyer, customers, and suppliers. Lastly, over 100 original, colored samples are attached to the described recipes. In this paper, the artifact’s contents will be disclosed, comprising recipes with attached samples and correspondence. Findings resulting from archive research will be included, contextualizing and placing the dyer in their urban and social context. The paper concludes by discussing its potential limitations and provides avenues for possible future research. Full article

This research investigates the suitability of printed polyamide 12 (PA12) and its dyed version to support cells in bioengineering applications. For this purpose, human gingival fibroblasts (hGF06) were cultured on PA-12 scaffolds that were 3D-printed by Multi Jet Fusion (MJF). The study examined the direct cultivation of cells on MJF-printed cell culture scaffolds and the effect of leachate of PA-12 printed by MJF on the cultured cells. The article presents research on the surface treatment of PA12 material used in 3D printing and the effect of automatic staining on cell vitality and proliferation in vitro. The study presents a unique device designed exclusively for staining prints made of the biocompatible material PA12 and demonstrates the compatibility of 3D-printed polyamide 12 parts stained in the novel device with a nutrient culture medium and cells. This novel PA12 surface treatment for biomedical purposes does not affect the compatibility with the culture medium, which is essential for cell viability and proliferation. Fluorescence microscopy revealed that mitochondrial fitness and cell survival were not affected by prolonged incubation with clear or dyed PA12 3D-printed parts. Full article

Natural dyes offer a bio-based opportunity to support the attractive coloration of textile fabrics made from natural fibers like cotton, wool, hemp, and many other textile materials. They can be part of a strategy to realize fully bio-based textiles and clothing materials. In line with this statement, the following study investigates the use of wood extracts for dyeing cotton fabrics. Specifically, extract powders of logwood (Haematoxylon campechianum L.), brazilwood (Caesalpinia spp.), and quebracho wood (Schinopsis lorentzii) are used. The aim of the study is to evaluate which colorations can be obtained by the application of those wood extracts and what fastness properties are reached. For this, different modified process parameters and mordants are evaluated. The dyeing process is modified using different mordants based on iron and aluminum salts. These mordants are applied in pre-, meta-, or post-mordant procedures. The color and fastness properties of prepared textile samples are determined by spectroscopic measurements, color measurements, washing procedures, and a Xenotest for measuring the light fastness. Ultimately, it is shown that a broad range of colorations can be realized through different combinations of wood extracts and mordanting procedures. Notably, stronger color depths are reached with pre- and meta-mordanting compared to post-mordanting. Good wash fastness is obtained for some color shades. However, with post-mordanting, better wash fastness can be achieved. The light fastness of the realized samples is only moderate to low. In conclusion, it can be stated that dyes from wood extracts are excellent materials to dye natural fibers if they are combined with the right mordanting agent in pre- or meta-mordanting procedures. The present study is therefore a good proof-of-concept for the realization of fully bio-based colored textile materials. Full article

Wood staining is a crucial technique for enhancing the decorative effect of wood. Different mordants and mordant processes can influence the staining effect of wood. In this study, three types of mordants and mordant methods were selected to improve the color difference and colorfastness to the washing of poplar veneer, using green peanut pigment as the dye. An orthogonal test was conducted to investigate the effects of mordant temperature, mordant time, and mordant concentration on color difference and colorfastness to washing. Range and variance analysis were employed to determine these properties’ main factors. A fuzzy comprehensive evaluation method was used to evaluate and optimize the color difference value and colorfastness of washing. The results revealed that all three factors had significant impacts on both color difference and colorfastness to washing during the process of mordant staining. The optimal process conditions (temperature, concentration, time) for achieving desirable staining effects on poplar veneer were determined as 50 °C, 0.8%, and 2 h, respectively. Furthermore, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and X-ray diffraction (XRD) analyses demonstrated that the dye formed complexes with poplar wood, enabling it to adhere to wood grain apertures and tube walls effectively. Mordant treatment increased the crystallinity of stained wood significantly while improving its overall staining performance considerably. This study provides substantial data support for future optimization processes involving natural pigment coal staining in wood. Full article

Mastering a colour—as such, its ‘domestication’—involves a weft of technological and symbolic relationships encompassed in the human ability to reproduce a visible colour using the techniques of textile dyeing. The Regimento dos panos or Regimento dos trapeiros (‘regulation of fabrics’ or ‘regulation of drapers’), published in 1573 and expanded in 1690, is a document made up of 107 chapters aiming to standardise the various stages of the production chain of woollen goods in Portugal. In the sections relating to the finishing of fabrics, the regulation carefully details the dyeing of the colour black. The main aim of this text is to discuss the four recipes presented in that document. The system presupposed a phase exogenous to the rules, since the fabrics had to be previously dyed blue (‘celestial blues’) by means of successive immersions of the cloth in a vat with indigo. The dyeing itself was achieved by mixing mordants and auxiliaries (alum, tartar, iron sulphate, and tannins) with a red dye (madder). The main conclusion is that the formulae presented do not constitute, in their general principles, a characteristic Portuguese methodology. In addition, the article includes an inventory of the raw materials used for dyeing in the Early Modern Age, produced, through a qualitative method, through cross-reference with other manuscript and printed sources, as well as an interpretation of their social and economic importance, and a systematisation of the types of Portuguese wools. Full article

Natural dyes derived from plants offer a sustainable alternative to synthetic dyes for textile coloration. This study examined the extraction of natural dyes from Conocarpus erectus L. leaves and their application on wool and silk fabrics. Aqueous extraction in an alkaline medium was used to obtain dyes from raw leaves, which were then applied to pre-mordanted silk and wool fabrics by applying the ultrasonic-assisted exhaust dyeing method. The dyed fabrics were evaluated for color strength (K/S) and CIELAB color coordinates. The color fastness (washing, rubbing, and light), ultraviolet protection factor, mosquito repellency, and antibacterial activity were established using standard testing protocols. The surface morphologies of silk and wool were examined using scanning electron microscopy. Interestingly, the dyed fabrics displayed good color strength and color fastness properties. Moreover, the dyed wool samples revealed satisfactory antibacterial activity against Gram-negative (E. coli) and Gram-positive (S. aureus) in both qualitative and quantitative assessment methods, good ultraviolet protection in terms of UPF, and good mosquito repellency against Aedes aegypti. This study for the first time presented the application of a medicinal plant (Conocarpus erectus L.) in the field of textile dyeing and finishing. Hence, the use of Conocarpus erectus L. leaf dyes offers significant results on wool and silk fabrics and contributes to sustainable functional textile production. Full article

The subjects of this research are the burial clothes of Polish King Sigismund III Vasa and his wife Constance, which were woven and embroidered with silk and metal threads. Fragments of the textiles underwent spectroscopic, spectrometric, and thermogravimetric analyses. The hydrofluoric acid extraction method was improved to isolate various classes of dyes from the textile samples that had direct contact with human remains. High-performance liquid chromatography, coupled with diode array and tandem mass spectrometry detectors with electrospray ionization (HPLC-DAD-ESI-MS/MS) facilitated the detection and identification of colorants present in the textiles. Cochineal, indigo-, madder-, orchil-, and tannin-producing plants were identified as the sources of dyes used. Scanning electron microscopy with an energy-dispersive X-ray detector (SEM-EDS) was employed to identify and characterize the silk fibers and mordants and the metal threads. The presence of iron, aluminum, sodium, and calcium in the silk threads suggests their potential use as mordants. The analysis of the metal threads revealed that most of them were made from flattened gilded silver wire, with only a few being cut from a sheet of metal. Typical degradation mechanisms of metal threads were shown, resulting from both burial environment and earlier manufacturing process, and the use of the textiles in clothing, i.e., a significant loss of the gold layer was observed in most of silver gilt threads, caused by abrasion and delamination. The results of the thermal analysis confirmed the presence of silk and silver threads in the examined textiles. Full article

This paper presents a comprehensive study on a novel ultrasound-assisted extraction process for Rosa canina, utilizing both dry and fresh fruits, and explores the potential application of Rosa canina extraction as a natural dye and functional agent for cotton fabrics. The ultrasound-assisted extraction employed different solvents, including distilled water, methanol, and a water/methanol mixture (50/50% v/v), conducted at 60 °C for 60 min. The extracted compounds were characterized through ultraviolet–visible (UV-Vis) spectroscopy and high-performance liquid chromatography with ultraviolet spectroscopy (HPLC-UV) analysis to assess the chemical composition. Textile applications were then performed using bio-mordant chitosan in a pre-mordanting process, and the treated cotton fabrics underwent analysis for surface chemistry and chemical composition using Fourier-transform infrared spectroscopy (FTIR). Untreated and treated fabrics, both with and without mordant, were evaluated for their UV protection and antibacterial properties. Color measurements and dyeability properties of the extractions were also assessed. Furthermore, waste solutions from textile applications were analyzed by UV-Vis spectroscopy to investigate the potential transfer of active compounds to the fabrics. Results indicate that Rosa canina, as a plant-based extract, holds significant potential for sustainable dyeing and functional finishing of cotton fabrics. Full article

Antoine Janot and Paul Gout were 18th-century master dyers who specialised in the piece-dyeing of fine wool broadcloths manufactured in Languedoc (southern France) for exportation to the Levant. They wrote treatises, similarly entitled Mémoires de Teinture (Memoirs on Dyeing), illustrated with dozens of dyed textile samples. Janot’s is dated 1744, and Gout’s is dated 1763. These books are full of extremely valuable information, which is unique to its time: the books are composed of carefully described recipes for every colour, each originally preceded by a sample swatch. The yellows of both master dyers made from weld (Reseda luteola L.), belonging to recipes described as Jaune (yellow), were reproduced. The influence of the ingredients, in both the mordanting and dyeing baths, was assessed, and the timings for both baths, which in many recipes are not clear, were tested. This provided key knowledge on the technological processes for dyeing with weld from these 18th c. French masters. The resulting reference samples were preliminarily analysed by a multi-analytical approach. Their chromatic specifications, expressed in the CIEL*a*b*, were compared with those in the Mémoires. Moreover, the influence of the recipe on the percentages of the chromophores was assessed by HPLC-DAD. It was found that the bran and tartar in the mordanting bath influence the final obtained colour and that lime is essential to obtain a bright yellow. Full article