Properties Of Dyes Research Articles

Investigation of the effects of laser radiation on silk fabrics dyed with kermes insect (Kermes vermilio Planchon)

In this study, the dyeing properties of a natural dye extracted from the kermes insect on silk were examined. Insect dye at different concentration rates of 5%, 10%, and 15% wt was applied to silk fabrics mordanted with alum [KAl(SO4)2.12H2O] and iron-(II) sulfate [FeSO4.7H2O]. Then, the Nd:YAG laser device was used to investigate the laser radiation effects on the color of the fabric. The dyed fabrics were analyzed by different analytical and technical methods. The RP-HPLC-DAD method was used for the identification of the coloring compounds of fabrics dyed with kermes. The color coordinates and fastness values of rubbing, washing, and light were investigated. Overall, the fastness results were excellent. SEM-EDX was performed for morphological examinations and CIEL*a*b* color values were measured for colorimetric examinations after laser radiation.

Study on the Dyeing and Fastness Properties of Ash Veneer with Acid Dyes.

As an alternative to raw wood, processed timber can help reduce costs and environmental damage while meeting the needs of various fields that require building materials possessing the sensibility of raw timber. Veneer wood is positioned as a high-value-added product owing to its elegance and beauty, and it is used in various building-related fields, such as interior decoration, furniture, flooring, building interior materials, and lumber. Dyeing is necessary to enhance its esthetic appearance and expand its use. In this study, we compared and analyzed the dyeability of ash-patterned materials using acid dyes and evaluated their performance as interior materials. The ash-patterned material was dyed using three types of acid dyes, and a comparative analysis was performed. The most suitable dyeing conditions were 80 °C, 3 h, and 3% o.w.f. Furthermore, the effect of pretreatment before the dyeing process, the effect of methyl alcohol solvent during dyeing with acid dyes, and the dyeability of veneers dyed under various temperature and time conditions were also compared and analyzed. Resilience to daylight, resilience to rubbing, fire resistance, and flame retardance of the selected material were evaluated as being suitable for use as a building material for interiors.

Polymethine Dyes Based on 2,2-Difluoro-1,3,2-dioxaborine: a Minireview

Aim. To summarize and analyze literature data on the polymethine dyes containing the 2,2-difluoro-1,3,2-dioxaborine ring.Results and discussion. Boron difluoride complex of β-diketone (2,2-difluoro-1,3,2-dioxaborine, F2DB) is a unique structural motif endowing organic compounds with prominent physicochemical properties, such as a strong fluorescence and high mo-lar attenuation coefficients. Incorporation of the F2DB core into a polymethine chromophore either as an end-group or as an integral part of the polymethine chain allows obtaining dyes with exceptional characteristics, highly appealing for design of up-to-date functional materials. This review focuses on the synthesis and spectral properties of the F2DB-containing polymethines along with the latest advancement in the synthesis of highly fluorescent polyanionic polymethines. A brief discussion of the effects of the structural modification of the π-conjugated system on the photophysical properties of dyes is included.Conclusions. The literature on the F2DB-containing polymethines demonstrates a high potential of the F2DB core for the development of strongly fluorescent and intensely absorbing dyes.

Effectively controlling luminescent property and the ESIPT behavior of styryl dyes by atomic substituent

In view of the unique luminescent characteristics, excited state intramolecular proton transfer (ESIPT) materials have attracted lots of attention. Considering the influence of different atomic substituents on the photophysical properties and ESIPT reaction, we systematically studied the molecular and electronic properties of styryl dyes with O, S and Se substituents by the quantum chemistry methods. The results indicated that the ESIPT energy barrier of styryl dyes reduced with atomic substituents (O < S < Se). And potential energy curves (PECs) showed that the ultra-fast ESIPT reaction of styryl dyes could be controlled and regulated by atomic substituents. In addition, the styryl dyes had a large stokes shift, which reproduced the double fluorescence properties. It meaned that the enol and keto structures of three styryl dyes interconvert by ESIPT channel under the photoexcitation. Therefore, the special optical properties of styryl dyes could improve their application as potential biological imaging.

Different Dyeing Properties in Nonaqueous Dyeing Systems for Various Wool Fibers

Different Dyeing Properties in Nonaqueous Dyeing Systems for Various Wool Fibers

Dyeing properties of polylactic acid fabric with disperse dyes of different structures using decamethylcyclopentasiloxane as non‐aqueous media

AbstractPolylactic acid (PLA) fibre, as a renewable and biodegradable synthetic polymer, is attracting increasing attention in the field of textiles. However, there are still some problems associated with PLA fibre dyeing, with a traditional water bath using disperse dyes restricting its industrialisation. Waterless dyeing, as a green and environmentally friendly dyeing method for PLA fibre, is expected to replace the traditional water bath dyeing method. However, the disperse dyes suitable for PLA fibre are different from those that are suitable for traditional poly(ethylene terephthalate) fibre. In the current study, the waterless dyeability of PLA fibre using disperse dyes with different chemical structures, and decamethylcyclopentasiloxane (D5) as the media, was investigated. First, the optimal dyeing process conditions of dye concentration, dyeing temperature, dyeing time and liquor ratio for PLA waterless dyeing were determined. The results indicated that the most suitable dyeing process conditions were: a dye concentration of 5%, dyeing temperature and time of 120°C and 40 minutes, respectively, and a liquor ratio of 1:10. Next, PLA was dyed with 10 disperse dyes with different structures using the determined optimum dyeing process conditions to compare their dyeing properties. The results showed that there were obvious differences in the K/S values for PLA dyed with dyes of different structures. The K/S values for PLA dyed with monoazo structure dyes were significantly higher than those for anthraquinones and heterocyclic structure dyes. Disperse dyes with a monoazo structure are suitable for PLA waterless dyeing. This study provides a research basis to develop suitable dyes for waterless dyeing PLA using D5 as the media.

Doping nanocellulose crystal with poly(vinyl alcohol) for water‐resistant composite fibers with enhanced mechanical and dyeing performances

AbstractAcetalization has been commonly adopted to realize the improvement on the water resistance and mechanical properties of poly(vinyl alcohol) (PVA) composite fibers. However, acetalized PVA fibers only have a very low concentration of hydroxyl groups on the surface and thus have poor dyeing performance. In this case, hydroxyl‐rich nanocellulose (NC) offers a fascinating solution for improving the dyeing properties of PVA fibers. Herein, we developed NC/PVA composite fibers by wet spinning the aqueous mixture of NC and PVA followed with acetalization treatment. Compared with pure PVA fibers, NC/PVA composite fibers had a significant improvement of 36% and 53% in terms of tensile strength and elongation at break when the NC content was 10 wt%, respectively. More importantly, when the NC content reached 20 wt%, the K/S value of the composite fiber was approximately threefold greater in comparison to that of the PVA fiber, indicating that the dyeing performance of NC‐modified composite fibers was greatly improved. This work provides a simple and easy method to possess PVA fibers with excellent dyeing properties and mechanical properties, demonstrating the potential to realize the application of PVA fibers in more practical scenarios.

Photosensitive Dye as an Ideal Peroxymonosulfate Activator for Efficient Self-Degradation: A Novel Idea of Using Waste to Treat Waste.

Commonly used peroxydisulfate (PS) or peroxymonosulfate (PMS) activation methods have been limited in their practical application due to certain drawbacks, such as high cost, high energy consumption and secondary pollution. In this study, a catalyst-free alizarin green (AG) self-activating PMS catalytic system was constructed based on photosensitization properties of dye, which ultimately achieved efficient degradation of the dye activator, also the target pollutant. Here, 52.5% of the 100 mL mixture of 10 mg/L AG decomposed within 60 min with 1 mM PMS under visible-light irradiation, thereby showing a strong pH adaptation. Mechanism of AG self-activating PMS was revealed that the photo-excited AG can effectively transfer photo-induced electrons to PMS for its activation, which generates reactive oxidizing species dominated by singlet oxygen (1O2), and supplemented by hydroxyl radical (•OH), superoxide radical (O2•-) and sulfate radical (SO4•-) to realize the efficient self-degradation of the dye pollutants. Moreover, such self-catalytic system operated well under natural sunlight irradiation, indicating the great application potential in the actual wastewater treatment. Herein, photosensitive dye acted as an ideal PMS activator realizing its efficient self-degradation, which provides a novel idea of "using waste to treat waste" for developing wastewater treatment process in a high-efficiency and low-consumption way.

Biological Activity of Naphthoquinones Derivatives in the Search of Anticancer Lead Compounds.

Naphthoquinones are a valuable source of secondary metabolites that are well known for their dye properties since ancient times. A wide range of biological activities have been described highlighting their cytotoxic activity, gaining the attention of researchers in recent years. In addition, it is also worth mentioning that many anticancer drugs possess a naphthoquinone backbone in their structure. Considering this background, the work described herein reports the evaluation of the cytotoxicity of different acyl and alkyl derivatives from juglone and lawsone that showed the best activity results from a etiolated wheat coleoptile bioassay. This bioassay is rapid, highly sensitive to a wide spectrum of activities, and is a powerful tool for detecting biologically active natural products. A preliminary cell viability bioassay was performed on cervix carcinoma (HeLa) cells for 24 h. The most promising compounds were further tested for apoptosis on different tumoral (IGROV-1 and SK-MEL-28) and non-tumoral (HEK-293) cell lines by flow cytometry. Results reveal that derivatives from lawsone (particularly derivative 4) were more cytotoxic on tumoral than in non-tumoral cells, showing similar results to those obtained with of etoposide, which is used as a positive control for apoptotic cell death. These findings encourage further studies on the development of new anticancer drugs for more directed therapies and reduced side effects with naphthoquinone skeleton.

Spectral and photophysical characteristics of asymmetric polymethine dyes in polyurethane matrices

Effects of the polymer matrix polarity on the spectral and photophysical properties of asymmetric polymethine dyes were investigated. Asymmetrical cyanines of the LDS (laser dye styryl) series were used, which were introduced into elastic polyurethane matrices by an auxiliary solvent. Polymer media were synthesized by: a polyaddition reaction based on macrodiisocyanate from oligoethylene glycol adipinate, hexamethylene diisocyanate, trimethylolpropane, and a photopolymerization reaction of oligourethane acrylate with benzoin isobutyl ether. Polyurethane polarity influence on the absorption and luminescence band maxima, and the Stokes shift of the dye spectra was studied, and the obtained spectral parameters of dyes in the polymer matrices were compared with the corresponding characteristics of their ethanol solutions. The observed spectral peak positions of the absorption and luminescence bands, changes in the Stokes shift value for the LDS dyes in different environments indicated the presence of positive solvatochromism. The presented results demonstrated the possibility of the significant increase in photostability of asymmetric polymethine dyes in the polymer polyurethane matrix of high polarity, obtained by means of the polyaddition reaction.

Process maximization of salt free reactive dyeing on cotton using Taguchi approach

This study optimized the salt free reactive dyeing process using the Taguchi approach. Dyeing of cotton fabric with reactive dyes is popular because of its bright and brilliant color in various shade ranges. Cationization with ALBAFIX-WFF and the dyeing process on cotton fabric was carried out using the exhaust method. To determine the optimum process conditions, two types of multiple characteristic parameters, including the single characteristic value conversion method and the process maximization method, were used on the basis of color strength (K/S) and wash fastness. The single characteristic value conversion method confirmed that the optimum process condition was a cationization temperature of 40 °C and a dyeing pH of 11. Most importantly, the optimal conditions were confirmed by the process maximization method as a concentration of ALBAFIX-WFF 30 g/L, cationization temperature at 80 °C, dyeing pH 12, and material-to-liquor ratio (M:L) of 1:5. More suitable dyeing properties are also achieved by the process maximization method.

Theoretical investigation of the effect of different π‐spacers on the performance of dye‐sensitized solar cells based on quinoline

AbstractHerein we report a heterocyclic organic system to be used in dye‐sensitized solar cells. We propose 9 D‐π‐A compounds in with N,N‐diphenyl quinoline‐6‐amine as the electron donor, cyanoacrylic acid as the electron acceptor, and various conjugate systems of thiophene is used as a π‐spacers. The studied substance systems are calculated by density functional theory (DFT) method with 6‐311G(d) basis set. This study focuses on examining the effect of the π bridge on the properties of the molecule. The structural parameters of the molecular geometry were optimized, the HOMO and LUMO energies were calculated and analyzed in detail. In addition, the absorption wavelength, excitation energy, vibration intensity and electron transfer were calculated through the time‐dependent density functional theory (TD‐DFT) method. The result shows that replacing thiophene ring by 3,4‐ethylenedioxythiophene (EDOT) significantly improved the properties of dye. Compounds B12 and B23 have not only small HOMO‐LUMO gap but also good charge transfer (small reorganization energies) and optical properties (high LHE).

Third-order nonlinear optical properties of unsymmetrical tetrazole-based dyes and study the effect of electrostriction on reverse saturation absorption

Third-order nonlinear optical properties of unsymmetrical tetrazole-based dyes and study the effect of electrostriction on reverse saturation absorption

Dyeing of Wool with Sappan Wood Natural Dye Using Metal Salts for Enhancement in Color and Fastness Properties

ABSTRACT In this study, we explore the dyeing properties of the extract of sappan wood natural dye for coloration of wool yarn to find the potential use of natural dyed wool yarn in the development of eco-friendly textiles. Different characterizations were used to know the chemistry of sappan wood dye and its interaction with metal salts and wool. Interestingly, we found that metal salts, which are called as mordants in reference to unmordanted dyed sample, play an important role in fixing the dye molecule on wool as well as in creating different shades with a variety of hues and tones. The typical color of fabric dyed with extracts of sappan wood without mordant varies from yellowish to red. Light yellowish shades were obtained in case of aluminum sulfate-mordanted samples, whereas yellowish shades were obtained in case of ferrous sulfate mordant. Light colorfastness of the premordanted dyed samples was relatively better than that of the unmordanted dyed samples. The wash fastness of all samples mordanted as well as unmordanted shows color change fairly good to good level, whereas the color staining on wool and cotton was found to be negligible.

Bioinspired gold coated phage nanosomes for anti-microbial and anti-cancer theranostics

We report a unique bioinspired phage nanosome as a biological template for tuning the NIR absorbance of gold nanoparticles (ФNSAu) coated on its surface. Spectroscopical analysis revealed that the presence of phage significantly enhances the optical properties of encapsulated dyes, rendering them excellent imaging agents. In vitro, studies showed the excellent photothermal transduction efficacy of the developed ФNSAu in combination with a chemotherapeutic drug, Mitoxantrone (ФNSAuM). ФNSAuM mediated photothermal therapy (PTT) using a 690 nm laser exhibited excellent anti-microbial activity against E. coli and C. albicans. In vitro and in ovo studies using zebrafish embryos revealed excellent biocompatibility, no/minimal cardiotoxicity, and enhanced internalization of phage-based nanosomes when compared with respective liposomal controls. When tested against 4T1 cell lines, the synthesized ФNSAuM exhibited significant synergistic anti-cancer activity with enhanced ROS generation and subsequent mitochondrial damage. The blood vessel rupturing potential of ФNSAuM mediated PTT has been demonstrated using an in ovo chick chorioallantoic membrane (CAM) assay, thus proving it as a potential photothermal agent. Overall, the developed phage-based nanosomes facilitated enhanced PTT efficacy, thereby showing an encouraging potential for anti-microbial and anti-cancer theranostics.

Relationship between reactive group chemistry and printing properties of heterofunctional reactive dyes via screen printing

Screen printing of cotton fabric using newly synthesized azo reactive dyes was carried out in the present study. Functional group chemistry and its effect on the printing properties of cotton fabric by varying the nature, number and position of reactive groups of synthesized azo reactive dyes (D1–D6) was studied. Different printing parameters (Temperature, alkali and urea) and their effect was explored on the physicochemical printing properties e.g., fixation, color yield, and penetration of the dyed cotton fabric. Data revealed that dyes with more reactive groups and having linear and planar structures (D-6) showed enhanced printing properties. Spectraflash spectrophotometer was used to evaluate the colorimetric properties of screen-printed cotton fabric and results showed superb color buildup. Printed cotton samples displayed excellent to very good ultraviolet protection factor (UPF). Presence of sulphonate groups and excellent fastness properties may entitle these reactive dyes as commercially viable for urea free printing of cotton fabric.

슬로우 패션을 위한 블루베리 염색성에 관한 연구

Blueberries were used to test the solution concentration, dyeing temperature, and pH concentration on cotton, linen, wool, and silk fabrics, which are natural fibers, as an eco-friendly method for slow fashion. In blueberry dyeing, cotton, linen, wool, and silk fabrics were commonly found to have better dyeing properties as the solution concentration increased, and overall, they were found to have the most stable and excellent dyeing properties at pH 3. Cotton and linen fabrics had better dyeing properties as the dyeing temperature decreases. Cotton fabrics represent various colors of green, purple, and blue depending on the dyeing conditions, and linen fabrics represent purple colors. The higher the dyeing temperature, the better the dyeing properties of wool and silk fabrics have better dyeing properties. The surface color of wool represents a brown color with yellow. In silk fabrics, the pH concentration is a very important factor rather than the solution concentration and the dyeing temperature, and the surface color ranges from red-purple to brown colors. Cotton, linen, wool, and silk fabrics all have a low grade of fade in colorfastness to washing, but the stain is all excellent in grades 4-5. Colorfastness to rubbing was found to be quite excellent, and Colorfastness to light was found to have a low overall grade.

IMPROVEMENT OF THE DYEING PROPERTIES OF 100% POLYESTER FABRICS VIA CHITOSAN APPLICATION

In this experimental study, it was aimed to research the possibilities of improving the dyeing properties of 100% polyester fabrics. For this purpose, the polyester fabrics were pretreated with sodium hydroxide and chitosan. The hydrophility of the pretreated fabrics were researched and they were then dyed with acid dye at 90 ⁰C. After dyeing processes, the CIEL*a*b* color values, color strength, fastness properties (to washing, water, perspiration, and rubbing) of dyed samples were investigated, and the bursting strength of the undyed and dyed samples was also tested. The results showed that it is possible to improve the dyeing properties of 100% polyester fabrics via chitosan application and that the polyester fabrics can be dyed with acid dyes at low temperatures after being cationized with chitosan following the NaOH application.

A stain color normalization with robust dictionary learning for breast cancer histological images processing

Microscopic analyses of tissue samples are crucial for confirming the diagnosis of breast cancer. The digitization of these samples has led to the development of computational systems that can assist pathologists. However, these systems may face limitations owing to color variations in the images. Normalization studies have been widely conducted to address these issues, but there is still a need for new proposals that take into account the biological properties of dyes and tissues. This study presents a novel method for normalizing hematoxylin and eosin-stained histological images by estimating the color appearance matrices and density maps of the stain. The proposed method offers contributions in terms of pixel selection and weight definition to improve the color estimation of histological images. Besides, to the best of our knowledge, no previous studies have evaluated normalized images considering both handcrafted and learning features. Breast cancer images with significant color variations were used to evaluate this approach and the results demonstrated its effectiveness and efficiency. The average values of FSIM, NIQE, and QSSIM were up to 0.9866, 3.4298, and 0.9655, respectively. Compared with other normalization techniques, the proposed method showed an increase of up to 5.9261, with the largest difference observed in the amount of noise added, as indicated by the NIQE metric. To determine the impact of normalization on feature extraction, the evaluations included an analysis of both color and deep-learned features. These experiments showed that all evaluated methods harmed the separation of breast cancer samples by color features. In contrast, the deep-learned features resulted in less complex classification problems, especially with the proposed normalization. This technique also reached one of the lowest processing times, nearly 6 s with the largest image from the databases.

Indotricarbocyanine dyes relevant for photodynamic therapy and their radicals: Substituent effects studied by optical and electrochemical methods

Photodynamic therapy is an effective and minimally invasive treatment method for cancer. A deeper understanding of the photocytotoxicity mechanism of cyanine dyes is necessary for the development of more efficient photosensitizers. We combine electrochemistry, optical and ESR spectroscopy, and quantum chemical calculations to study indotricarbocyanine dyes relevant for photodynamic therapy. The incorporation of 4-meso-chloride and a 3,5-o-phenylene bridge into the polymethine chain results in a hypsochromic shift of the absorption spectrum by ca. 30 nm and in a downward shift of the frontier orbitals energy levels by 0.1–0.3 eV. In addition, such substitution imparts stability to the electrogenerated radical dications of the dyes. The presence of 4-meso-chloride and a 3,5-trimethylene bridge in the polymethine chain causes the absorption spectrum to shift bathochromically by almost 40 nm and the HOMO–LUMO energy gap to decrease by ca. 0.1 eV. The radical dication of the dye with such substitution is particularly stable and exhibits improved electron delocalization. The radical dication of the dye with an unsubstituted polymethine chain is unstable due to its propensity to form dimers. The substituents at the nitrogen atoms are shown to have almost no influence on the optical and electrochemical properties of the indotricarbocyanine dyes. The radical dications of the dyes with an o-phenylene bridge can oxidize bromide ions, unlike the radical dications of the dyes with an unsubstituted polymethine chain or with a trimethylene bridge. The reported data can be used to develop new indotricarbocyanine dyes with desired characteristics.