Glebionis coronaria (L.) Cass. ex Spach (Asteraceae)- a new fabric dye with potential antibacterial properties

The paper elucidates first ever report on Glebionis coronaria (L.) Cass. ex Spach as a new dyeing agent with high antibacterial activity. Glebionis coronaria (L.) Cass. ex Spach which is also known as Garland/Crown Daisy belonging to the flowering plant family Asteraceae has been identified as a new precursor/candidate to produce highly efficient natural textile dye and a potential antibacterial agent. Natural dye from garland daisy was extracted from the dried petals using DCM and MeOH solvent system. Change in mordants yielded 12 different shades of colours. Spectroscopic analysis of these extracts revealed the presence of carotenoids and flavonoids pigments and hence giving varied shades of yellow, greenish yellow colours (Code No. is assigned to each colour). Alum and stannous chloride have been found to give bright colours while ferrous sulphate gave dark shades of colour. Antibacterial activity of the extracts was studied against non-pathogenic bacteria's, Staphylococcus aureus (Gram-positive bacteria) and for the first time for Aeromonas sp. (Gram-negative bacteria). Two different concentrations of 10 ​mg/ml DCM and methanol extracts using methanol as solvent were tested. Both DCM and methanol extracts have shown inhibition in Aeromonas sp. while only DCM extract was inhibiting S. aureus. The flower extracts has not been evaluated till date for its dyeing properties with different mordants along with their bactericidal activity. Therefore, our present work was to extract natural dye from the flowers of Glebionis Coronaria (L.) Cass. ex Spach. and to do a detailed study.     

Application of phenolic compounds as natural dye extracted from date-pits: dyeing studies of modified acrylic fibres

This research work involves the dyeing of acrylic fabric with natural dye extracted from date pits powders using Soxhlet extraction process. The effect of dye bath pH, salt concentration, dyeing time and temperature were studied. The optimal dyeing conditions where pH 4, 0 g/L salt, 60 min, and 80 °C. The COD and the BOD5 of the residual dye bath were measured and it was shown from the registered values that the residual dye bath presents an acceptable rate of organic discharge.     

Investigation of the dyeing properties of cotton fabrics and wool yarns using Prunus persica leaf extract

In this study, the dyeing properties of cellulose fabric and wool yarn were investigated using Prunus persica (Peach) leaf extracts. For this concept, the cotton fabrics and wool yarns were subjected to pre–, meta– and post– mordanting processes in the presence of FeSO₄, CuSO₄ and AlK(SO₄)₂ mordants. The studies were carried out using medium pH. Color analyses of the dyed samples were done and the results were evaluated in terms of wash, rubbing and light fastness values. The color codes were determined with Pantone Color Quide, and K/S and L1 a1 b1 values were detected with color measurement spectrophotometer, and also washing–, crocking– fastness levels were evaluated using gray scale. As a result, it was detected that wool yarns exhibited better dyeing potential than cotton fabrics and highest color strength values were obtained using pre–mordanting method. For wool yarns, high color strength were achieved in the presence of AlK(SO₄)₂ mordant.     

Influence of Neem oil pretreatment on the dyeing and antimicrobial properties of wool and silk fibers with some natural dyes

Wool and silk fibers pretreated with neem oil and dyed with chlorophyll, saffron red and yellow natural dyes using economic methods such as microwave heating and ultrasonic energy. The effect of neem oil concentrations on color strength (K/S) was measured. The results indicated that, wool and silk fibers pretreated with neem oil recorded higher color strength values than the untreated fibers. Fastness properties and the color yield of the dyes under investigation on wool and silk fibers were evaluated. The results indicated that, color fastness to rubbing, washing and perspiration of all dyes are excellent to good and are approximately the same in microwave and ultrasonic method. The antimicrobial activity against bacteria and fungi were tested, and the results indicated that the samples pretreated exhibited higher inhibition percent than the untreated fibers. The morphologies structure of the untreated and treated wool fibers were examined by scanning electron microscopy (SEM). The untreated samples have a rough surface. The pretreated samples of wool fibers were swelling compared to the untreated fibers .The diameter of the fibers increased and have smooth and even surfaces. The changes in the surface morphology due to the effect of active ingredients of treatment with neem oil. This behavior as swelling and increase in diameter of the fibers leads to high penetration of the dyes in the fibers.     

Eco-dyeing and functional finishing of wool fabric based on Portulaca oleracea L. as colorant and Musa basjoo as natural mordant

Biomass energy is the most acknowledged renewable resource due to its universality, richness, and renewability. This study utilized a Portulaca oleracea L. plant as a natural colorant for wool fabric dyeing with a high color yield at optimum extraction and dyeing conditions. To evaluate the dyeing mechanism and feasibility of the extracted dyes, we analyzed and characterized the molecular structure and nano-level particle size. The dyeing kinetics and the morphology of dyed fabrics were integratedly explored; the adsorption process of wool fabric on natural colorant molecules was increasingly in line with the pseudo-second-order kinetic adsorption model. Further, the dyeing effects of wool fabrics were compared to that of Musa basjoo mordant and synthetic dyes to confirm the superior color depth (K/S value 23.53), biological function as anti-ultraviolet (UPF value 253.47), and anti-bacterial activity (antibacterial rate of Staphylococcus aureus/Escherichia coli was 71.3%/37%). Our findings provide a feasible scheme for providing deep color and biological activity to wool fabrics. This has broad application prospects in the field of eco-friendly textile materials.     

Sustainable process for the pretreatment and dyeing of Eri silk

The green process route for pre-treatment and dyeing of Eri silk is proposed and investigated in this study. The natural plant-based saponins were extracted from Sapindus mukorossi by aaqueous extraction technique. Extracted Saponins showed a high emulsification index (68), low surface tension (41 dyne/cm), mild foaming (200 mm), and a slightly acidic pH, these characteristic properties are considered to be best suited for the processing of silk. The degumming was performed using Sapindus extract liquid with a concentration of 10% (owf) for 60 min at a temperature of 95 °C. The Eri silk degumming produced similar weight loss (4.63%), water absorbency (3 s) and optical properties - whiteness (80.33), yellowness (2.27) and brightness (70.05), as compared to the conventional process. The tensile strength (8.28 kgf)) and elongation (34.29%) was found to be better than the properties of the fabric processed with conventional chemical processing. The dyeing of degummed and bleached Eri silk with natural dyes showed comparable colour depth and uniformity of shade as compared to the conventional chemical processing. The overall fastness performance of dyed Eri silk was in line with the industry standards. Advanced characterization techniques such as FTIR was used for structural analysis of treated Eri silk.     

Development of a novel method for investigation the uptake behaviors of acid dye on silk fabric at various flow statuses in a coloration circular pipe

A novel methodology and a special fluid dynamics coloration machine were successfully constructed, and then the uptake behaviors of an acid dye on silk fabric under different flow statuses and parameters were explored for the first time. The obtained results show that the traditional additions of auxiliaries will not significantly change the kinematic viscosity of the dyeing bath. As coloration flow status was in laminar, transitional and turbulent flow, respectively, the dye uptake behaviors on the silk fabric were significantly different. Meanwhile, decreasing the bath pH value and increasing the temperature of the dyeing bath had a significant positive effect on the dye uptake behaviors in different flow statuses. Additionally, coloration in laminar or transitional flow preferred a relatively low dosage of neutral salt, which benefits to a cleaner production. Additionally, high coloration performance with color-fastness to washing and rubbing of the dyed silk at 4-grade or above was achieved under different flow statuses. The results further clearly indicate that the constructed method and self-built fluid dynamics coloration machine are helpful to investigate dye uptake behavior in different flow statuses, and are potentially beneficial to an efficient process and parameters design for cleaner production in textile coloration.     

一种复合脱色剂在印染废水中的应用研究

以甲醛、双氰胺、醋酸钠、氯化铵、氯化铝等为原料制备了一种印染废水脱色絮凝剂T-1。采用福州某纺织印染有限公司的印染废水为处理对象,以脱色率为主要考核指标,讨论了T-1的投加量、pH值、废水温度等对絮凝效果的影响。实验结果表明,双氰胺-甲醛缩聚物对印染废水具有优良的脱色絮凝效果,当投加量为100mg/L,废水温度为30℃,pH=8时,处理效果最佳,色度去除率达70%,COD去除率为78.3%。而且其絮凝性能明显优于聚合氯化铝(PAC)、聚合硫酸铝(PAS)絮凝剂。     

The effect of cation size on ion pairing of methyl orange dye with tetraalkylammonium and benzyltrialkylammonium ions in aqueous solution

Formation constants have been measured by a solvent distribution method for the ion pairing of an arene sulfonate, methyl orange dye, with two series of quaternary ammonium ions: R₄N⁺(R=Et,n-Pr,n-Bu, andn-Pent) and C₆H₅CH₂R₃N⁺ (R=Me, Et,n-Pr,n-Bu,n-Pent, andn-Hex). Ion pairing increases dramatically as the length of the R group increases beyond butyl. Using a hard-sphere model for contact ion pairs, it is estimated that coulombic attraction contributes about –kT to the binding free energy and decreases slightly with increasing size of R₄N⁺. Other factors related to solvation effects, of which cosphere overlap predominates, contribute from –2kT to –7kT of binding energy. Plots of logK for association as a function of cation size show an inflection with decreasing slope between R=propyl and R=butyl. Possible causes for the inflection are considered.     

Natural Dyeing of Modified Cotton Fabric with Cochineal Dye

Natural dyes are not harmful to the environment owing to their biodegradability. For dye application to textiles, salts are necessary as mordant or electrolytes and make an environmental impact. In this paper, the influence of cationization during mercerization to the dyeing of cotton fabric with natural dye from Dactylopius coccus was researched. For this purpose, bleached cotton fabric as well as fabric cationized with Rewin OS was pre-mordanted using iron(II) sulfate heptahydrate (FeSO₄·7H₂O) and dyed with natural cochineal dye with and without electrolyte addition. For the characterization of surface changes after cationization, an electrokinetic analysis on SurPASS was performed and compared to pre-mordanting. For determination of dye exhaustion, the analysis of dye solution was performed on a UV/VIS spectrophotometer Cary 50 Solascreen. Spectrophotometric analysis was performed using a Datacolor 850 spectrophotometer, measuring remission ”until tolerance” and the whiteness degree, color parameters, color depth (K/S), and colorfastness of dyed fabric were calculated. Levelness was determined by visual assessment. Cationized cotton fabrics showed better absorption and colorfastness. Pre-mordanting and cationization showed synergism. The electrolytes improved the process of dye absorption. However, when natural dyeing was performed on cotton fabric cationized during mercerization, similar chromacity, uniform color, and colorfastness were achieved with and without electrolyte, resulting in pure purple hue of cochineal. For achieving a violet hue, pre-mordanting with Fe-salt was needed. Therefore, salt can be reduced or even unnecessary, which makes this process of natural dyeing more environmentally friendly.     

Synthesis of new reactive dyes containing commercial UV-absorbers with enhanced simultaneous dyeing and anti-UV properties for cotton fabric

Two new reactive anti-UV dyes were synthesized based on two commercial UV-absorbers, ethyl 4-aminobenzoate for dye 1 and 4-aminobenzophenone for dye 2, which were incorporated in a structure modified from commercial reactive dye CI Reactive Red 198 (dye 3). Optimum exhaustion and total fixation values were achieved at 80 ​g/l sodium sulphate for dye 1 and 60 ​g/l sodium sulphate for dye 2, 20 ​g/l sodium carbonate at 70 ​°C for dye 1 and 80 ​°C for dye 2 and 60 ​min fixation time for both dyes. The two new reactive dyes exhibited higher dyeing properties and UPF values than the commercial reactive dye over all the dye concentrations studied. The new reactive dye 1 achieved the highest exhaustion, total fixation and UPF values. The fastness properties obtained for all the dyeings ranges from good to excellent.     

Photovoltaic properties of the flavonoid-based photosensitizers: Molecular-scale perspective on the natural dye solar cells

The molecular modification and the effects of the gas and water media on the ability of some flavonoids as the photosensitizers in the natural dye-sensitized solar cells were theoretically investigated. According to the results, water increases the electrophilicity of the dyes and weakens the dye/TiO₂ coupling, prohibiting the electron injection toward TiO₂. A longer path for charge transfer and a less electron-hole overlap for dihydroxychromens elevate the electron transfer more efficient than trihydroxychromen-based flavonoids. However, the presence of water molecules within an increment in the  OH groups in the flavonoid structures improves their spectroscopic properties, which is related to decrement in the gap of the frontier molecular orbitals and increment in the oscillator strength. Also, such favorable structural effects and influence of the water medium on the polarizability and excited-state lifetime have emerged. According to the energy conversion efficiency, water is a favorable solvent for dihydroxychromen-based flavonoids. Finally, different analyses on the structural geometries, excited-state, lifetime within the kinetics, and dynamics of the photovoltaic processes were performed and discussed.     

Fabricating superhydrophobic surfaces by molecular accumulation of polysiloxane on the wool textile finishing

In the present study, a novel and simple method of obtaining superhydrophobic surface through the migration of organic siloxane segments in the acrylate side chains to the outmost layer and forming the nano-protuberance on the micro-roughness wool fabrics was described. The chemical compositions and morphologies of the untreated/treated fabrics were characterized by the scanning electron microscopy and X-ray photoelectric energy spectroscopy. Meanwhile, the surface hydrophobicity was evaluated by the static contact angle measurement. The scanning electron microscopy photographs showed that the fiber surfaces of the treated fabrics were obviously granulated, and a wax film covered on the fibers could be observed. X-ray photoelectron spectroscopy analyses and static contact angle measurement further testified that the component of the wax was almost siloxane and that the surfaces of the treated fabrics had superhydrophobic property. The above results indicated that this method could be extended to prepare superhydrophobic surfaces by migrating the low-surface-energy matter and fabricating the nanoscale roughness on the micro-roughness material surfaces.     

Synthesis of an electron-rich aniline-containing dye and its dyeing behaviors on silk through a three-component Mannich-type reaction

Under the guidance of the finding that the tyrosine residues in proteins could undergo three-component Mannich-type reactions with formaldehyde and electron-rich aniline-containing compounds,which forms covalent bonding connections between the protein of interest and the aniline with high levels of selectivity under relatively mild conditions,an orange aromatic primary amine-containing acid dye AMODB was designed and readily synthesized.The molecular structure was characterized by FTIR,~1H NMR,mass spectrometry and elemental analysis.The synthesized dye and a similar control dye(C.I.Acid Yellow 11) without primary amine groups were applied to dye silk fabric by three dyeing processes:Mannich-type dyeing(with and without the addition of formaldehyde) and acidic dyeing.Their washing and rubbing fastness properties with different dyeing methods were examined and compared.It was found that the dyed silk fabric with AMODB by the Mannich-type dyeing showed higher color depth,better anti-stripping ability to DMF and better washing fastness than those of the dyed silk fabric with C.I.Acid Yellow 11 by acidic dyeing due to the covalent bond formation between the dye chromophore of AMODB and silk fiber.In addition,mild Mannich dyeing conditions suitable for silk(AMODB at 3%owf,75:1 liquor-to-goods ratio,dyebath pH 5.5,30℃,10 h) were provided.     

Influence on electrochemical impedance and photovoltaic performance of natural DSSC using Terminalia catappa based on Mg-doped ZnO photoanode

In this paper, we report the successful fabrication of a novel dye-sensitized solar cell (DSSCs) using Mg doped ZnO as photoanode and natural dye Terminalia catappa as sensitizer. We synthesized Mg doped ZnO nanoparticles at different Mg concentrations (2%, 4%, 6%, and 8%) by employing a simple solvothermal route. The structural, morphology, composition and optical investigations of synthesized Mg doped ZnO nanoparticles are carried out using XRD, FE-SEM, EDAX, TEM, SAED, FTIR and UV–visible measurements. The XRD results confirmed the formation of hexagonal-wurtzite structure for the Mg doped ZnO nanoparticles and increase of crystalline size with increasing dopant concentration up to 6% is observed. FESEM analysis indicated a gradual change in the surface morphology with increasing Mg concentration and the size of the nanoparticles are slightly reduced at higher Mg concentration. The HRTEM images and SAED pattern also confirmed the formation of wurtzite hexagonal phase of ZnO. The band gap energies calculated from the UV–visible spectra using Tauc's plots indicated decrease of band gap energy with dopant concentration. The DSSCs fabricated using Mg doped ZnO photo-anodes and Terminalia catappa sensitizer showed higher efficiency at higher Mg concentration and observed increase in efficiency is discussed based on slower charge carrier recombination and higher carrier life time as evidenced from the electrochemical impedance analysis.     

Ultrasonic assisted improved extraction and dyeing of mordanted silk fabric using neem bark as source of natural colourant

Natural products with therapeutic nature are nowadays warmly welcomed in textiles. Current study is concerned with isolation of tannin from neem bark (Azadirachta indica) and its application onto silk fabric. For improvement in shades, chemical & bio-mordants have been employed at optimal dyeing conditions. It is found that methanolic extract of pH 5 obtained 8 g dye powder after US Treatment for 30 min has given high color strength if used to dye irradiated silk for 65 min at 75 °C. Bio-mordanting using herbal plants has improved the color characteristics as compared to chemical mordants used. ISO standards for color fastness reveal that herbal based bio-mordants have improved the rating from good to excellent as compared to chemical mordants used. It is concluded that US treatment has not only isolate the colorant for neem bark under mild condition but also given excellent characteristic using bio mordants onto silk fabrics.     

New spectrophotometric method for the determination of some drugs with iodine and wool fast blue BL

A simple, sensitive and selective method is proposed for the spectrophotometric determination of drugs, viz. ampicillin, penicillin V, amoxycillin, cloxacillin, cefadroxil, ceftezoxime, griseofulvin, streptomycin, nicoumalone and acebutolol HCl, based on their reactivity with iodine. The method involves the addition of excess iodine of known concentration to the drug in the presence of NaOH and the unreacted iodine is determined by the measurement of the decrease in the absorbance of the dye wool fast blue BL (λ_max=540 nm) which was found to be the most suitable of several dyes tested. This method was applied for the determination of drug contents in pharmaceutical formulations and enabled the determination of the drugs in microgram quantities (0.8–9.6 μg ml⁻¹). No interferences were observed from excipients and the validity of the method was tested against reference methods.     

A novel squaraine dye with squaramide as a scaffold and the colorimetric detection of amine

A novel unsymmetrical squaramide-linked squaraine dye(SQ) has been synthesized through squaramide 3 and semisquaraine 6. The molecular structure of SQ has been characterized by ~1H NMR,IR and MS.Due to the influence of the hydrogen bond and the solvent effect,SQ exhibits unique spectral properties compared with typical squaraine dyes.For its excellent ability of binding primary amine,SQ is a promising receptor of recognizing primary amine.     

Study on optimizing dyeing of cotton using date pits extract as a combined source of coloring matter and bio-mordant

In this research, extraction of colouring matter from date pits powder was conferred by conventional and ultrasonic methods. Phenolic compounds present in the resulted extract were identified by HPLC analysis. Total phenolic, total flavonoid and total metallic contents were quantified; and the highest levels were obtained in case of ultrasonic extraction process at a frequency of 25 kHz. The different resultant extracts were diluted with distilled water and unified to a polyphenolic content of 48 mg per 100 mL. Dyeing results have been discussed as a function of the bio-metallic contents present in the extract. It was found that the highest colour strengths and the better fastness properties were registered in case of dyeing experiments developed using the ultrasonic extracts. Those above results could be due to the highest metallic content present in the ultrasonic extracts, which has functioned as a bio-mordant properly extracted from date pits powder.     

Synthesis and characterization of metal complexes of azo dye based on 5‐nitro‐8‐hydroxyquinoline and their applications in dyeing polyester fabrics

New Mn(II), Ni(II), Co(II) and Cu(II) complexes of an azo dye ligand based on p ‐phenylenediamine with 5‐nitro‐8‐hydroxyquinoline were synthesized and characterized using elemental analysis, inductive coupled plasma analysis, molar conductance, powder X‐ray diffraction, thermogravimetric analysis, magnetic moment measurements, and infrared, ¹H NMR, electron ionization mass and UV–visible spectral studies. The spectral and analytical data reveal that the azo dye ligand acts as a monobasic bidentate ligand via deprotonated OH and nitrogen atom of the quinoline ring. The data support the formulation of all complexes with a 2:1 ligand‐to‐metal ratio, except the Mn(II) complex that has a mononuclear formula. All complexes have an octahedral structure. The molar conductance data reveal that all the metal complexes are non‐electrolytic in nature. From the X‐ray data, the average particle size of the ligand and its complexes is 0.32–0.64 nm. The colour fastness to light, washing, perspiration, sublimation and rubbing of the prepared ligand and its complexes on polyester fabrics and colorimetric properties were measured. The results reveal that the ligand and its complexes have a good to moderate affinity to polyester fibres.