Eco-friendly Finishing Research Articles

Antimicrobial Finish for Cotton/polyester from Natural Bio-extracts

This study develops and applies sustainable antimicrobial finishes derived from Azadirachta indica (Neem), Butea monosperma, and Litchi chinensis leaf extracts to 50/50 cotton/polyester blend fabrics. The antimicrobial efficacy of these finishes was evaluated, revealing a 100% reduction in microbial growth after 22 hours and six days. Before and after applying antimicrobial finish FTIR, SEM and fabric aesthetic properties were checked. The antimicrobial finish was applied by the pad dry cure method and finish was fixed by using of polyurethane binder. In case of aesthetic properties (stiffness, smoothness appearance) antimicrobial finish had positive effect on 50/50 cotton/polyester. The treated fabrics also exhibited significant increases in stiffness (p < 0.001, h2 = 0.85). Additionally, the smoothness appearance of treated fabrics was assessed, revealing a slight decrease in smoothness appearance ratings as compared to untreated controls group, although this decrease was not statistically significant (p = 0.29). Fourier Transform Infrared (FTIR) spectroscopy revealed changes in functional groups, indicating successful finish application. Scanning Electron Microscopy (SEM) micrographs displayed surface modifications and filament breakage. The results were analyzed through ANOVA. The fabric properties were checked by using AATCC standard test methods. These eco-friendly finishes offer promising alternatives to synthetic antimicrobials, enhancing textile sustainability and consumer safety. The findings of this study contribute to the development of sustainable and environmentally friendly textile finishes.

Assessment of the Biodegradability and Compostability of Finished Leathers: Analysis Using Spectroscopy and Thermal Methods.

In this study, the biodegradation properties of leather treated with various finishing chemicals were evaluated in order to enhance the sustainability of leather processing. We applied advanced analytical techniques, including FT-IR, thermogravimetric analysis (TGA), and solid-state NMR spectroscopy. Leather samples treated with different polymers, resins, bio-based materials, and traditional finishing agents were subjected to a composting process under controlled conditions to measure their biodegradability. The findings revealed that bio-based polyurethane finishes and acrylic wax exhibited biodegradability, while traditional chemical finishes like isocyanate and nitrocellulose lacquer showed moderate biodegradation levels. The results indicated significant differences in the biodegradation rates and the impact on plant germination and growth. Some materials, such as black pigment, nitrocellulose lacquer and wax, were beneficial for plant growth, while others, such as polyurethane materials, had adverse effects. These results support the use of eco-friendly finishes to reduce the environmental footprint of leather production. Overall, this study underscores the importance of selecting sustainable finishing chemicals to promote eco-friendly leather-manufacturing practices.

Eco-friendly shrink-resist finishing of wool through synergistic effect of disulfide bond reducing agent and papain

The environmental benefits of utilizing protease as a biocatalyst for wool shrink-resist finishing have been widely recognized. However, the efficacy of individual protease treatment is unsatisfactory due to its incapability towards the outermost cuticle layer of wool fibers that contains hydrophobic fatty acids. In order to weaken the structural integrity of the highly cross-linked scales and promote the enzymatic anti-felting, sodium sulfite and tris (2-carboxyethyl) phosphine hydrochloride (TCEP) were employed in combination with papain, respectively, aiming at obtaining a low shrinkage without unacceptable fiber damages. Based on the synergistic effect of papain and TCEP, the edges of wool scales were slightly destroyed by the reduction of disulfide bonds, accompanied by enzymatic hydrolysis of the keratin component. Through the controlled reduction and hydrolysis of wool scales, satisfactory anti-felting result was achieved without causing severe damage to the fiber interiors. In the presence of 0.25 g/L TCEP and 25 U/mL papain, the area shrinkage of wool fabric decreased to approximately 6 %, with a low strength loss of less than 8 %. Meanwhile, the dyeing behavior of the wool fabric under low-temperature conditions was dramatically improved, leading to decreased energy consumption during production. The present work provides an alternative for eco-friendly finishing of wool fabrics, which can be applied commercially.

Core 2.0 Nebulization Technique - A Sustainable Denim Finishing Approach

Sustainability has emerged as a key concept in the modern techniques of washing and treating denim. The clothing industry, specifically the denim washing sector, confronts substantial sustainability issues due to its impact on water pollution and the generation of large quantities of chemical waste. This research aims to investigate the long-term sustainability of the nebulization process in the context of denim finishing. The goal is to assess the dependability of the technology as a feasible option by demonstrating its effectiveness using environmental impact measuring software. The environmental impact assessment assesses the ecological consequences of clothing across four fundamental areas: water usage, chemical utilisation, energy consumption in the production process, and labour implications. The aforementioned methods proved to have low energy and water demands, resulting in less waste and pollution. This study evaluated several aspects of nebulization on denim and concluded that nebulization is a beneficial method for applying eco-friendly finishing.

Biopolymer-loaded plasma-mediated multi-functional finishes of polypropylene fabrics

Polypropylene (PP) has unique competitiveness with other synthetic fibers due to its suitable spinnability, availability of raw materials, and low processing cost. PP fabric exhibits excellent chemical, physical, and mechanical properties, such as a light texture, adequate tensile strength, and resistance to most chemicals. However, the absence of reactive functional groups in PP fiber, besides its high crystallinity, results in hydrophobic surface, low affinity to dyestuffs, and poor antistatic properties, which restrict its use in the clothing field. Herein, a water- and energy-saving, eco-friendly finish is proposed to render PP desired properties suitable for textile applications. The surface of PP fabric was activated using oxygen and nitrogen plasma radiations. The plasma-irradiated PP fabric was post-treated with two renewable eco-friendly proteinic biopolymers, namely gelatin and sericin, in the presence and absence of a crosslinking agent. The effects of different process conditions on the properties of the modified PP, including the duration of plasma exposure, the concentration of biopolymer, and treatment temperature were monitored. The affinity of the treated PP fabric towards anionic and cationic dyes was evaluated. The findings of this study demonstrated that the comfort attributes of the plasma/biopolymer-finished fabrics, such as the induced antistatic properties, wettability, and ultraviolet protection, were remarkably improved. The plasma-mediated biopolymer-finished PP fabrics were found dyeable with cationic and anionic dyes. The change in the chemical and morphological structures of PP fabrics was monitored using Fourier transform infrared spectroscopy, scanning electron microscopy, and energy dispersive X-ray spectroscopy.

Nanobubble Technology for A Water-Repellent Treatment on Cotton Fabrics: A Comparative Study

Recently, a significant interest in eco-friendly textile products and processes has been noted among consumers and producers. In this respect, nanobubble technology is emerging as a green alternative. In this study, water-repellent cotton fabrics were produced with exhaustion and nanobubble technology (e-flow method) using a short-chain fluoropolymer. The currently most developed substituents are based on molecules with short fluorine carbon chains. The wettability, mechanical properties, air permeability and treatment durability were evaluated. The untreated and treated cotton fabrics were analyzed with ATR-FTIR (Fourier transform infrared attenuated total reflectance) and SEM (scanning electron microscopy) to reveal chemical and morphological modifications. The obtained results show that cotton samples treated with short-chain fluoropolymers, nontoxic and eco-friendly finishing chemicals, and nanobubble technology have good water repellence and good washing durability. Due to their size and structure, nanobubbles possess distinct properties that make them particularly effective at improving water quality, enhancing water treatment processes, and improving productivity in industrial applications. Nanobubbles have a strong negative surface charge that keeps them stable in liquid, prevents them from coalescing, and enables them to physically separate small particles and droplets from water, such as emulsified fats, oils, and grease.

Influence of cryogenic grinding surface on fatigue performance of carburised 27MnCr5

Automotive transmission components are subjected to cyclic loads and, thus, must have a reliable fatigue performance. Since fatigue cracks nucleate at the surface, it is necessary to guarantee that its surface integrity accomplishes the required specifications. Typically, those components are finished by wet grinding after carburising heat treatment. However, there is an increasing demand to reduce pollutants and hazardous lubricants in the industry, and eco-friendly finishing operations have been highly encouraged. To this end, it is necessary to understand the effect of these novel finishing processes on surface integrity and, consequently, on fatigue behaviour. This study aims to assess the surface integrity and the fatigue performance of cryo-ground surfaces of 27MnCr5 steel, extensively used in fabricating shafts and gears for gearboxes. Fatigue specimens for pure torsion tests were initially case-hardened and afterwards finished using two different cryogenic grinding conditions applying liquid N2 and, as a reference, using the conventional wet grinding process. First, the surface integrity was analysed in terms of texture, residual stresses, microstructure, and microhardness. Second, the batches of specimens were tested under pure torsion fatigue. Surface residual stress relaxation was also measured during fatigue tests. Finally, fracture surfaces were observed to identify crack initiation sites and establish correlations with the surface integrity. Specimens produced by cryogenic and conventional wet grinding did not show microstructural defects or hardness reductions in the carburised layer. All conditions induced compressive residual stresses, and they barely relaxed during fatigue tests. Compressive residual stresses induced by cryogenic grinding were 10–20% lower than those generated by conventional wet grinding. This decrease resulted in a minor reduction of the fatigue resistance (4–6%) compared to the wet grinding. Importantly, this study demonstrates that with a slight geometrical radio correction in the design of the mechanical components (around 2.2%), cryogenic grinding generates pieces with the same fatigue strength as conventional grinding. Therefore, it confirms that cryogenic cooling could be a potential solution to replace pollutant coolant/lubricant fluid in grinding operations.

Rendering Viscose Fabrics Dye-able with Basic and Acid Dyes Using Citric Acid and Chitosan Nano Particles Based Finishing Formulation

ABSTRACT The innovation anticipated here is the use of our previously prepared chitosan nanoparticles in conjunction with citric acid and sodium hypophosphite for rendering viscose fabrics dyed and finished concurrently in one step with dual classes of dyes, namely basic and acid dyes, using a pad-dry-cure process. This was done to see the effect of the aforementioned eco-friendly finishing formulation on creating dual anchoring sites onto finished fabrics for dye-ability using Basic Red 2 and Acid Orange 7, which have no direct affinity to viscose fabric. So, different concentrations of CA, CNPs, and dyes were mixed into a viscose fabric cross-linking formulation together with a set concentration of SHP (50% based on weight of CA concentration) and cured at 170°C for 2 minutes. Citric acid is predicted to react with the hydroxyl groups in viscose and CNPs to produce ester crosslinking and/or to form an inter-ionic attraction with the amino groups of CNPs. The latter was responsible for viscose fabrics dye ability with Basic Red 2 by anchoring the free carboxyl groups in citric acid, as well as their dye ability with Acid Orange 7 by anchoring the residual amine groups in CNPs.

Performance Enhancement of the Digital Printed Cotton Fabric through Ecofriendly Finishes

ABSTRACT Digital textile printing has emerged as a sustainable alternative to the conventional screen printing. Similar to other forms of coloration, digitally printed cotton fabric also needs finishing to overcome the inherent drawbacks of the cotton fabric. However, research on the finishing of the digital printed fabric is very limited and focused on non-sustainable finishes. In the first instance, this paper optimizes the recipe of the pre-printing process. Then, this paper investigates the performance of the digitally printed cotton fabric using three sustainable and formaldehyde free cross-linkers, three different softeners, C8-free oil and water repellent, and halogen free flame-retardant. This study applies these finishes on the steamed and non-steamed digitally printed fabric samples. The paper tests the performance of the finished digitally printed fabric in terms of key finishing properties. The results show that the proposed sustainable finishes have significantly improved the performance of the digitally printed fabric as compared to the reference non-finished digitally printed sample.

Sustainable Finishes for Healthcare Apparels

The conventional textile finishing process used to consume a high amount of water, chemical and energy source which leads to more hazardous waste material and polluting the environment. To replace these conventional methods, working towards sustainable manufacturing is more consideration for the need of an hour. In the field of medical textile, the finishes used for manufacturing the health care apparels should enhance the desired properties that the patient and the health care personals need. For this purpose, the advanced and eco-friendly finishing process has been developed. Thus in this paper, the sustainable and eco-friendly finishing process used in the field of medical textile has been discussed in detail.

Degumming silk by CO2 supercritical fluid and their dyeing ability with plant indigo

Degumming silk by CO₂ supercritical fluid and their dyeing ability with plant indigo

Eco friendly antimicrobial finishing of textiles using bioactive metabolite from endophytic Streptomyces fradiae CQLW against bio deterioration

Biodeterioration of fabric made of natural fibre is an inevitable threat for the textile industry. Many antimicrobial finishing with synthetic chemical are been in practice but the wash out effluent from the industry pollutes the environment and also becomes a cause for antimicrobial resistance in microbes at the exposed environment. Hence the present study is designed to identify a natural antimicrobial substance from the group actinobacteria that can be used as an ecofriendly finishing on cotton textiles. To accomplish the task endophytic actinobacteria were isolated from medicinal plants and screened for the production of antimicrobial compound against the biodeteriorating microbes viz. Bacillus subtillis, Bacillus megaterium, Pseudomonas aeruginosa and Pseudomonas fluorescence. The cotton fabric coated with bioactive crude culture filtrate using the dip-dry method according to the American Association of Textiles chemist colourists (AATCC) protocol was analyzed for its potentiality in actively inhibiting the growth of microbes by AATCC 90, AATCC100 and shake flask reduction methods. Results showed that finished fabric had good antibacterial activity than untreated fabric. Anti adhesive property and wash test results revealed that coated textiles were effective in preventing biofilm formation and without binder coating remained up to five wash cycles.

Water repellent treatment for cotton fabrics with long-chain fluoropolymer and its short-chain eco-friendly alternative

As the long-chain fluorochemical molecules used to obtain water and stain repellent textiles persist in the environment, chemical suppliers are trying to develop new products in order to find ecological alternatives. The current most developed substituents are based on molecules with shorter fluorine-carbon chains. In the current work, a long-chain fluoropolymer and its short-chain homologue were applied on cotton fabrics at different finishing conditions. Textile properties such as wettability, air permeability, mechanical properties and handle properties, for untreated and treated cotton samples were investigated. Laundering test was also performed to predict the durability of the finishing. The obtained results demonstrated that cotton samples treated with short-chain fluoropolymer show good water repellency and good washing durability. The use of short-chain fluoropolymers, as nontoxic and eco-friendly finishing chemicals, has allowed obtaining comparable performances to those produced with long chain fluoropolymer.

Environmentally sound approach for imparting antibacterial and UV-protection functionalities to linen cellulose using ascorbic acid

In this work, multifunctional linen cellulose fabrics were facilely developed by using an eco-friendly finishing formulations and the pad-dry/microwave fixation technique. Both reactant resin and citric acid have been employed as low- and zero-formaldehyde crosslinkers along with their proper catalyzing agents. Individual incorporation of ascorbic acid and selected phenolic compounds namely salicylic acid, resorcinol, and gallic acid, as natural active ingredient (AI-OH) along with PEG-400 or modified nonionic silicone-softener in ether- or ester-crosslinking formulation and their impacts on the performance, functional properties and degree of coloration of the finished fabrics were investigated. FTIR, SEM, and EDX analysis of selected samples were carried out. Results revealed that type of crosslinker, kind and concentration of active ingredient, as well as type of additive play an important role in the imparted functional properties. The durability of the imparted antibacterial and UV protection functional properties was confirmed by washing test.

Synthesis and Characterization of Freeze Dryer Chitosan Nano particles as Multi functional Eco-Friendly Finish for Fabricating Easy Care and Antibacterial Cotton Textiles

Antibacterial and easy care characteristics were imparted to cotton fabrics using multifinishing formulation comprising citric acid (CA) and chitosan nanoparticles (CNPs) as an eco-friendly finish. The latter of size around 60-100 nm were prepared through polymerization of meth acrylic acid (MAA) with chitosan using potassium permanganate as initiator and characterized using scanning electron microscope, transmittance electron microscope, Fourier transformer infrared spectroscopy, particle size analyzer, X-ray diffraction and thermo gravimetric analysis. Different factors affecting the degree of multifinishing treatment and their onset on fabric performance and antimicrobial activity were studied and optimized according to pad dry cure method. This was done to see the impact of chitosan nanoparticles to accomplish multifunction characteristics on cotton fabrics like reasonable strength loss, comparable wrinkle recovery angles, elongation at break, higher fabric stiffness and suitable durability in addition to antibacterial activity. It was seen from the attained results that; FTIR spectra and SEM micrograph showed the change in chemical structure and surface morphology of cotton fabric before and after finishing in absence and presence of chitosan nanoparticles. These fabrics parade antimicrobial activity against gram-positive and gram-negative bacteria tested even after 10 washing cycles. Mechanism of finishing of cotton fabric using citric acid and CNPs is identified.

Insight into multifunctional polyester fabrics finished by one-step eco-friendly strategy

Polyethylene terephthalate (PET) has been widely used in fabrics owing to its great mechanical properties, easy processability and quick drying. However, PET-based products always suffer from uncomfortable low sweat uptake and electrostatic charge buildup mainly due to its bad surface wettability. Moreover, porous fabrics may induce unfavorable mite and microorganism reproduction. Due to lack of reactive groups on the PET skeleton, it was very difficult to endow its surface hydrophilicity, antistatic properties, perdurable antimicrobial and anti-mite properties by conventional methods. In this work, we develop a one-step eco-friendly finishing strategy for PET fabrics through photochemical reaction using benzophenone group terminated quaternary ammonium salt (BP-QAS) as the finishing reagent. The as-finished PET fibers changed from incompact state to compact state due to the increased cohesive forces within individual fibers, resulting in improved tearing strength. The PET fabrics show significantly improved hydrophilicity, and antistatic properties. Furthermore, the as-finished PET fabrics exhibit excellent, durable broad-spectrum antimicrobial activities against gram-negative, gram-positive, drug-resistant bacteria and fungi. Moreover, our fabric shows long-lasting antimicrobial properties above AAA requirements after 50 laundering cycles. Usual PET fabrics generally have difficulty achieving AAA standards after 10 laundering cycles. In addition, our as-prepared fabrics showed excellent anti-mite activities against house dust mites based on disruption of the microbial and mite membrane due to oxidation stress, while no negative effects were observed for mouse and rabbit. The finished PET fabrics can be applied to multiple industries to prevent infectious diseases and improve public health, including but not limited to packaging, clothes, water treatment, and medical appliances.

Non-leaching bactericidal cotton fabrics with well-preserved physical properties, no skin irritation and no toxicity

We developed an isocyanate group containing quaternary ammonium salt (IQAS) as a potential antimicrobial finishing agent that can be stored in a high purity form for more than a year in dry environments to permit convenient transportation and storage. Additionally, we report a facile and eco-friendly finishing technique to fabricate durable antimicrobial cotton fabrics using IQAS as an antimicrobial finishing agent by a dipping–padding–drying process. IQAS was bound onto the surface of cotton fabrics by a covalent bond to obtain a cotton fabric with excellent bactericidal activity, tearing strength, breaking elongation, bending rigidity, water vapor permeability, surface roughness and smoothness. The antimicrobial rates of these fabrics reached 92.2% and 98.5% against gram-negative bacterium Escherichia coli and gram-positive bacterium Staphylococcus aureus, respectively, even after 50 laundering cycles. These values are much higher than the reference antimicrobial rates of AAA class antimicrobial fabrics, as well as those of conventionally finished cotton fabrics, indicating that the IQAS finished cotton fabrics maintained excellent antimicrobial activity even after long-term repeated launderings. Moreover, the results indicate that the IQAS-treated cotton fabrics could improve the breaking strength (increased by 13.5% in the warp direction and 20.3% in the weft direction), the bursting strength (increased by 11.9%), the air permeability (increased by 12.6%) and the hydrophilicity compared to untreated cotton fabrics. Additionally, our non-leaching antimicrobial cotton fabrics treated with IQAS were non-toxic and showed no skin stimulation. Therefore, IQAS and the antimicrobial finishing technique reported here have great potential applications in antimicrobial fabrics used in hospitals, hotels and other susceptible situations. An isocyanate group containing quaternary ammonium salt that permits convenient transportation and storage was developed as a potential antimicrobial finishing agent to fabricate excellent antimicrobial cotton fabrics with well-preserved physical properties and security using a dipping–padding–drying process.

PROCESS OPTIMIZATION OF ECO-FRIENDLY FLAME RETARDANT FINISH FOR COTTON FABRIC: A RESPONSE SURFACE METHODOLOGY APPROACH

The [Formula: see text]-methylol dimethyl phosphono propionamide (MDPA) flame retardant compounds are predominantly used for cotton fabric treatments with trimethylol melamine (TMM) to obtain better crosslinking and enhanced flame retardant properties. Nevertheless, such treatments are associated with a toxic issue of cancer-causing formaldehyde release. An eco-friendly finishing was used to get formaldehyde-free fixation of flame retardant to the cotton fabric. Citric acid as a crosslinking agent along with the sodium hypophosphite as a catalyst in the treatment was utilized. The process parameters of the treatment were enhanced for optimized flame retardant properties, in addition, low mechanical loss to the fabric by response surface methodology using Box–Behnken statistical design experiment methodology was achieved. The effects of concentrations on the fabric’s properties (flame retardancy and mechanical properties) were evaluated. The regression equations for the prediction of concentrations and mechanical properties of the fabric were also obtained for the eco-friendly treatment. The R-squared values of all the responses were above 0.95 for the reagents used, indicating the degree of relationship between the predicted values by the Box–Behnken design and the actual experimental results. It was also found that the concentration parameters (crosslinking reagents and catalysts) in the treatment formulation have a prime role in the overall performance of flame retardant cotton fabrics.

Dyeing of cotton yarn with marigold (Tagetes erecta) petals: An emphasis on pre-treatments and mordants

Natural dyes and eco-friendly finishing of textile fabrics is gaining popularity because of the consciousness of people in saving the ecology. Widely available resources in India have encouraged researchers in experimenting on extraction and application of dyes for textile colouration. The aim of the present experiment was to standardize a protocol for optimization of pre-treatment, mordanting and dyeing of cotton yarn with African marigold flower petals. Myrobolan, pomegranate rind and tamarind hull were utilized in different concentrations for pre-treatment. Effect of different mordants and pre-treatment concentrations on colour strength (K/S, L, a* and b*) parameters of the cotton yarn is was studied. Optimised pre-treatment concentrations, mordants and dyeing techniques on colour fastness parameters are also presented. Myrobolan followed by pomegranate rind pre-treatment produced darker and even shades on cotton yarns. Metallic salts viz., Stannous Chloride, Copper Sulphate and Ferrous Sulphate proved to produce shades with good to excellent colour fastness properties.

Effects of Commercial Nitrilase Hydrolysis on Acrylic Fabrics

This study aims to evaluate the hydrolytic activity of a commercial nitrilase and optimize nitrilase treatment conditions to apply eco-friendly finishing on acrylic fabrics. To assess the possibility of hydrolyzing nitrile bonds in acrylic fabric using a commercial nitrilase, the amounts of hydrolysis products, ammonia and carboxylate ions, were measured. The treatment conditions were optimized via the amount of ammonia. The formation of carboxylate ions on the fabric surface was detected by X-ray photoelectron spectroscopy and wettability measurements. After nitrilase treatment, ammonia was detected in the treatment liquid; thus, nitrilase hydrolyzed the nitrile bonds in acrylic woven fabric. The largest amount of ammonia was released into the treatment liquid under the following conditions: pH 8.0, <TEX>$40^{\circ}C$</TEX>, and a treatment time of 5 h. The formation of carboxylate ions on the acrylic woven fabric surface by nitrilase hydrolysis was proven by the increased O1s content measuring of XPS analysis. From comparison of the results of nitrilase and alkaline hydrolysis, the white index and strength of the alkali-hydrolyzed acrylic fabric decreased, whereas those of the nitrilase-hydrolyzed samples were maintained. The nitrilase hydrolysis improved the sensitivity of acrylic fabrics to basic dye similarly to alkaline hydrolysis without the drawbacks of yellowing and decreased strength caused by alkaline hydrolysis.