Hanan Elsisi

Two pyrazolone metal-complex dyes of the general formula [M(L)(H ₂ O)]· x H ₂ O (where M = Zn(II), x = 0, or Ni(II), x = 2; and H ₂ ₂L = 3-methyl-5-oxo-4-(phenylhydrazono)-4,5-dihydropyrazole-1-carbothioic acid amide) were successfully synthesized. The prepared complexes were characterized by FTIR, ¹ H-NMR, and UV–visible spectroscopy, as well as elemental analysis, mass spectrometry, and thermogravimetric analysis. The combined results indicate that the H ₂ L ligand coordinates in a di-anionic bidentate manner through the azo nitrogen and enolic oxygen atoms after deprotonation. However, a coordinated water molecule occupies an additional coordination site, resulting in a tetrahedral geometry around the metal (II) center in both complexes. Polyamide 66 fabrics were dyed using both the ligand and zinc metal dyestuff under supercritical carbon dioxide. However, nickel exhibits negligible solubility in supercritical carbon dioxide. The dyeing process was studied under varying conditions: The temperature ranged from 100 to 120 °C, the pressure ranged from 15 to 25 MPa, and the dyeing time ranged from 1 to 2 h. A pilot-scale experiment was conducted using the prepared dyestuff, demonstrating its potential for large-scale application on polyamide 66 fabric. The color uptake, expressed as color strength ( K / S ), was assessed, and the values obtained showed that the dyed polyamide 66 fabrics were significantly better. The color fastness properties of all the dyed fabrics were evaluated, yielding good results that demonstrated durability after 10 washing cycles. A notable enhancement in antimicrobial activity has been detected for both novel dyes and dyed fabrics. The results obtained in this study highlight the potential of metal-based dyes in supercritical laboratory- and pilot-scale dyeing of polyamide 66 fabric, highlighting the feasibility of scaling up the process.

Wool has been colored in supercritical carbon dioxide in a few trials, yielding only a small spectrum of colors, mostly orange and yellow, with minimal research on alternative color combinations. To further the industrial development of supercritical carbon dioxide (SCCO ₂ ) dyeing, a variety of dyes must be used to produce a diversity of colors. The material’s overall appearance is affected by shades of blue, yellow, and red. This study revealed the generation of new colors using three reactive disperse dyes with various colors: a blue dye derived from the anthraquinone parent body, a yellow dye with a pyrazole moiety, and a third, red, dye with an azo-thiazole moiety. These dyes and their blends were employed to dye wool fabric using supercritical carbon dioxide. The maximum K/S values were attained at 11.14 for the mixture of (blue dye: red dye 80:20), while the lowest K/S was indicated at 8.43 for (blue dye: red dye: yellow dye 1:1:2). However, the compatibility grade as per RCR values showed excellent values for the combination of three dyes. The dyed samples were evaluated for colorfastness, and the results showed that they retained their color well and were exceptionally durable after washing. The growing patterns in both the dyeing rate and build-up curves indicate good compatibility. Furthermore, desired hues of Teal, green, olive, gray, and reddish-brown can be created by combining blue, red, and yellow dyes in varied ratios in supercritical CO ₂ .

The global textile industry pollutes water significantly, primarily due to the harmful impact of dyeing processes. Researchers have explored different techniques to address this issue, such as utilizing supercritical fluid for dyeing. A new type of reactive disperse dyes has been developed by incorporating a transient anionic sulfatoethylsulfone group. The chemical structure was identified using spectral analysis, encompassing FT-IR, NMR, and elemental analysis. The dyeing process was performed on wool and nylon-6 using supercritical carbon dioxide. The dyed fabrics displayed deep hues and exceptional dye fixation. In the fastness experiments, significant findings were recorded for washing fastness (fading and staining grade of 4–5), rubbing fastness (wet and dry grade of 4–5), sweat (acidic and alkaline), and acceptable light fastness results for all the dyes. A significant improvement in antibacterial activity has been observed for both new dyes and dyed fabrics. The findings demonstrated that the suggested dyeing procedure is highly resistant to washing after five cycles.

Dyeing natural fabrics using supercritical carbon dioxide is challenging, especially without essential color hues. This work demonstrated that two newly developed reactive disperse dyes with distinct colors and shades were generated, one of which featured from the anthraquinone family and the other yellow, containing a pyrazole moiety. These new dyes and their combinations were used to dye cotton fabric using supercritical carbon dioxide and the highest K/S values were achieved at 8.73 for the mixture of (blue dye: yellow dye 80:20), however the lowest K/S was observed at 7.71 for (blue dye: yellow dye 20:80). The new dyes’ chemical compositions were identified using elemental and spectroscopic analyses. The effectiveness of these dyes and their mixtures for cotton dyeing was discussed. The dyed samples were tested for color fastness, and the results indicated that they had excellent color retention and were highly durable in washing. The increasing patterns in both dyeing rate and build-up curves show good compatibility. Furthermore, desirable shades of green can be achieved by mixing blue and yellow dyes at various ratios in supercritical CO₂. The compatibility test involves calculating color difference index values for dyed cotton fabrics by utilizing various ratios of a binary mixture of dyes. Furthermore, the dyes under study and dyed samples displayed superior antibacterial properties against gram-positive and gram-negative bacteria compared to certain antibiotics used as a control. These results aligned with the quality and eco-friendly standards required by the industry without the use of water.

It has become increasingly popular to replace chemically synthesized compounds with natural counterparts mostly found in natural sources, such as natural pigments. The conventional extraction processes for these compounds are limited by the toxicity and flammability of the solvents. To obtain pure extracts, it is always a longer process that requires several steps. Supercritical fluid extraction (SFE) is a cutting-edge green technology that is continuously increasing and expanding its fields of application, with benefits such as no waste produced, shorter extraction time, automation, and lower solvent consumption. The SFE of natural pigments has high potential in food, textiles, cosmetics, and pharmaceuticals; there are a number of other applications that can benefit from the SFE technique of natural pigments. The pigments that are extracted via SFE have a high potential for application and sustainability because of their biological and antimicrobial properties as well as low environmental risk. This review provides an update on the SFE technique, specifically as it pertains to the optimization of health-promoting pigments. This review focuses on antimicrobial pigments and the high efficiency of SFE in extracting pure antimicrobial pigments. In addition, the optimal conditions, biological activities, and possible applications of each category are explained.

Nowadays, consumers understand that upgrading their traditional clothing can improve their lives. In a garment fabric, comfort and functional properties are the most important features that a wearer looks for. A variety of textile technologies are being developed to meet the needs of customers. In recent years, nanotechnology has become one of the most important areas of research. Nanotechnology’s unique and useful characteristics have led to its rapid expansion in the textile industry. In the production of high-performance textiles, various finishing, coating, and manufacturing techniques are used to produce fibers or fabrics with nano sized (10⁻⁹) particles. Humans have been utilizing cotton for thousands of years, and it accounts for around 34% of all fiber production worldwide. The clothing industry, home textile industry, and healthcare industry all use it extensively. Nanotechnology can enhance cotton fabrics’ properties, including antibacterial activity, self-cleaning, UV protection, etc. Research in the field of the functionalization of nanotechnology and their integration into cotton fabrics is presented in the present study.

The COVID-19 pandemic has clearly shown the importance of developing advanced protective equipment, and new antiviral fabrics for the protection and prevention of life-threatening viral diseases are needed. In this study, selenium nanoparticles (SeNPs) were combined with polyester fabrics using printing technique to obtain multifunctional properties, including combined antiviral and antibacterial activities as well as coloring. The properties of the printed polyester fabrics with SeNPs were estimated, including tensile strength and color fastness. Characterization of the SeNPs was carried out using TEM and SEM. The results of the analysis showed good uniformity and stability of the particles with sizes range from 40–60 nm and 40–80 nm for SeNPs 25 mM and 50 mM, respectively, as well as uniform coating of the SeNPs on the fabric. In addition, the SeNPs—printed polyester fabric exhibited high disinfection activity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with an inhibition percentage of 87.5%. Moreover, a toxicity test of the resulting printed fabric revealed low cytotoxicity against the HFB4 cell line. In contrast, the treated fabric under study showed excellent killing potentiality against Gram-positive bacteria (Bacillus cereus) and Gram-negative bacteria (Pseudomonas aeruginosa, Salmonella typhi, and Escherichia coli). This multifunctional fabric has high potential for use in protective clothing applications by providing passive and active protection pathways.

This study aims to develop multifunctional pile cotton fabrics by implementing different compositions of lycra yarns with different densities of the cotton fabric under study. Highly dispersed silica nanoparticles (SiO₂ NPs) with small sizes—in the range of 10–40 nm—were successfully prepared and were analyzed using scanning electron microscopy (SEM). The particle size distribution of nano silica was determined via dynamic laser scattering (DLS) and measurements of its zeta potential. Cotton/lycra fabrics were treated using prepared SiO₂ NPs in presence of ethylenediaminetetraacetic acid (EDTA) as a crosslinking agent. Energy dispersive X-ray (EDX) analysis and scanning electron microscopy (SEM) were used to characterize the nano-treated fabrics and assure homogeneous dispersion of SiO₂ NPs on the cotton/lycra composites. Additionally, the nanoparticles were screened for their in vitro antibacterial activity against human pathogens such as Gram-positive Staphylococcus aureus and Bacillus cereus and Gram-negative Escherichia coli and Pseudomonas aeruginosa strains. The functional properties of the new composite pile cotton fabrics include excellent antibacterial, highly self-cleaning, and excellent UV protection factor (UPF) properties.