Experimental study on dyeing technical PET yarns having different TiO<Subscript>2</Subscript> contents

TiO₂ contents in yarns can influence color yield so that dyeing quality of industrial poly ethylene terephthalate (PET) yarns can be improved through the adjustment of TiO₂ contents. To evaluate the dyeing performance of color yield, the chips which included the different TiO₂ contents of 330, 550, and 1,100 ppm respectively were used to produce the yarns of different TiO₂ content by a spin-draft machine. The physical and structural properties of the yarns were measured to investigate effect of the TiO₂ contents on them. Dye uptake and dyeing rate were also evaluated using a colorimeter to compare the yarns having different TiO₂ contents. The experimental results showed that there were no appreciable variation in physical and structural properties among the yarn samples and no difference were observed among the dyed fabric samples with regard to dyeing uptake and dyeing rate. However, the color yield of dyed fabrics increased as TiO₂ contents decreased in the yarns especially when the fabric samples were dyed to pale shade. The physical reasoning could be proposed on why the yarns having low TiO₂ contents appeared to have higher color yield after dyeing.     

Antibacterial properties and color fastness of silk fabric dyed with turmeric extract

The use of non-toxic and eco-friendly natural dyes on textiles has received much attention due to the increased environmental awareness in order to avoid some hazardous synthetic dyes. In the present study, an eco-friendly approach was developed to impart color and antibacterial properties to silk fabrics dyed with turmeric extract as a non-toxic natural colorant. The natural colorant was extracted from Curcuma Longa rhizome. Copper sulfate, ferrous sulfate and potassium aluminium sulfate were applied in a pre-metallization process as mordanting agents. Antibacterial properties of treated fabrics were evaluated against common pathogenic bacteria, Staphylococcus aureus (Gram-positive) and Escherichia coli (Gram-negative). The effects of dye concentration and mordant types on the obtained color hues, antibacterial efficiency and color fastness of the fabrics were investigated. The results indicated that mordanted and dyed fabrics possessed desirable antibacterial properties. Complete antibacterial activity of the treated fabrics was obtained with 3 %owf (on weight of the fabric) copper sulfate. It was also shown that increasing the dye concentration could lead to a more efficient antibacterial activity on the mordanted dyed fabrics. An optimum level of the antibacterial activity was observed in the sample treated with 30 %owf of turmeric. Furthermore, the results of CIE L*, a*, b* values, FTIR, washing, light and rubbing fastnesses of the dyed fabrics were reported. The mordanted dyed silk fabrics exhibited desirable color fastness properties. These studies proved a direct relationship between the degree of antibacterial activity of the fabrics treated with turmeric and the metals ion concentration.     

Effect of nano SrTiO3 supporting nano TiO2 on self-cleaning of cotton fabric

This study reports the results of an investigation aiming at finding what affect nano titania (TiO₂) and nano strontium titanate (SrTiO₃) on self-cleaning of cotton fabrics. The photocatalytic activity of nano strontium titanate has been examined on cotton fabric under UV irradiation in various concentrations in mixing of nano titania. The amount of loaded nano titania and nano strontium titanate particles on cotton fabrics were investigated using X-ray fluorescence spectrometry (XRF) and crystallinity of coatings by X-ray diffraction spectroscopy (XRD). The treated cotton fabrics, which were stained with two common synthesized dyes, were exposed to 400 W UV radiation for 30 hours and their self-cleaning property was investigated by a reflectance spectrophotometer. Scanning electron microscope (SEM) images show pervasion of nano materials on the surface of the treated cotton. Adding nano strontium titanate to nano titania showed the most promising photocatalytic activity toward dye degradation.     

Dyeing and antibacterial properties of <Emphasis Type="Italic">Liriope platyphylla</Emphasis> fruit extracts on silk fabrics

Dyeing and antibacterial properties of a natural dye extracted from Liriope platyphylla fruit applied on silk fabrics have been studied. The total phenolic content (1109.13±69.02 mg), total flavonoid content (530.60±89.44 mg), and total anthocyanin content (492.26±77.79 mg) were measured in 100 g fresh weight of L. platyphylla fruits. In addition, ten anthocyanins and four flavanols were identified in L. platyphylla fruits by high performance liquid chromatography with diode array detection coupled with electrospray ionization mass spectrometry (HPLC-DAD/ESI-MS). A broad variation in color shade and color depth can be achieved with mixtures of dye extracts and metal mordants. Purple, blue, and pale green were main color shades of silk fabrics dyed with the extracts. The fastness of dyed silk fabrics except for control dyed fabrics against light, washing, and rubbing were acceptable with at least a grey scale rating of 3. The antibacterial activities of L. platyphylla fruit extracts were retained on dyed silk fabrics even after home washing 30 cycles. Mordanting with metal salt mordant had a positive effect on antibacterial activity of dyed silk fabrics in this study. Among them, aluminum and copper were the most effective mordants for improving antibacterial activity of silk fabrics dyed with L. platyphylla fruit extracts. The costs of natural dyeing of per silk fabrics kg by the extracts from L. platyphylla fruit were also calculated on laboratory scale.     

Durable multifunctional properties on acrylic fabric using nano TiO2 and polysiloxane

Producing fabric with multifunctional properties has been recently a center of research and utilizing nanoparticles is an efficient approach to gain this purpose. Here, nano TiO₂ photo catalyst and polysiloxane softener were utilized as stabilizer on the acrylic fabric to obtain soft handle, hydrophilic, and self-cleaning features on the fabric. The effect of various concentrations of nano TiO₂ and polysiloxane on the fabric handle, water droplet absorption time, and self-cleaning properties of the fabric has been mathematically modeled based on the response surface methodology (RSM). The optimized treatment conditions indicated that treated acrylic fabric with 2.19 % polysiloxane and 0.68 % nano TiO₂ produced the rigidity of 26.8 g.cm, water absorption time of 15.8 s and self-cleaning of ΔE _T *=18.1. Also increasing the concentration of polysiloxane enhanced both wettability and photoactive properties of nano TiO₂ treated acrylic fabrics. Further, the nano TiO₂/polysiloxane treated acrylic fabrics is significantly enable to absorb the light with wavelength lower than 400 nm and improve discoloration of C.I. Reactive Yellow 1.     

Nano-TiO<Subscript>2</Subscript> based multilayer film deposition on cotton fabrics for UV-protection

Nano-TiO₂ based multilayer nanocomposite films were fabricated on cationically modified woven cotton fabrics by layer-by-layer molecular self-assembly technique. Cationization process was used to obtain cationic surface charge on cotton fabrics. Attenuated total reflectance Fourier transform infrared spectroscopy analyses were used to verify the presence of cationic surface charge and multilayer films deposited on the fabrics. Scanning electron microscope micrographs of poly(sodium 4-styrene sulfonate)/TiO₂, nano polyurethane/TiO₂, and TiO₂/poly(diallyldimethylammonium chloride) multilayer films deposited on cotton fabrics were taken. With nano-TiO₂ based multilayer film deposition, the protection of cotton fabrics against UV radiation is enhanced. The UV protection durability of the self-assembled multilayer films deposited on the cotton fabrics was analyzed after 10 and 20 washing cycles at 40 °C for 30 min. Air permeability and whiteness value analysis were performed on the untreated and multilayer film deposited cotton fabrics. The effect of layer-by-layer deposition process on tensile strength properties of the warp and weft yarns was determined.     

Dyeing and fastness properties of vat dyes on meta-aramid woven fabric

meta-Aramid fibers have an excellent heat-resistant property and are widely used for protective clothings such as fire-fighter suit and racing suit. They can also be used as military uniforms such as flight suit or army uniform. Vat dyes are specially used for military uniforms owing to outstanding fastness properties, earth tone shade, and near infrared (NIR) camouflage. In this study, 100 % meta-aramid woven fabric was dyed with three vat dyes using an exhaustion method and their dyeing and fastness properties were investigated. Color yields of the vat dyes on the meta-aramid fabric were found to be dependent upon dyeing temperature, liquor ratio, amount of reducing agent, and amount of salt. Dyeing behavior of the vat dye on the meta-aramid fiber was very similar to that on cellulose fibers. It was found that the meta-aramid fabric dyed with 1% owf of C.I. Vat Green 1 satisfied the tolerance of the reflectance spectrum of forest green color in the Korean military standard. Thermal stability and mechanical property of the meta-aramid fabric did not significantly affected by the vat dyeing process. Wash and perspiration fastness was generally good but rubbing and light fastness was unsatisfied.     

Cross-cultural study of color sensation and sensibility for Korean traditional fabrics with natural indigo dyeing

This study focused on fabric planning for environment-friendly fashion products for the international market. In order to achieve this objective, some Korean traditional fabrics (Mosee and Myungjoo) with natural indigo dye were selected and they were evaluated in terms of subjective color sensation and sensibility by two cultural groups (Korean and American college students). Also, color preference for the natural dye fabrics by each cultural group was predicted by colorimetric properties, color sensation, and color sensibility factors. Most bluish fabrics dyed with natural indigo colorants were likely to provide a cold and strong sensation. There were partially significant differences in terms of color sensation among six fabrics. The color sensibility for the naturally dyed fabrics was classified into three factors: ‘Classic’, Romantic’, and ‘Unique’. The color sensibility factor ‘Classic’ was the dominant factor for the naturally dyed fabrics with indigo colorant. There were cultural differences in terms of color sensation and color sensibility factors between Korean and American university students. Color preference of dyed fabrics with natural indigo was found to be influenced mainly by the color sensibility factors among colorimetric properties, color sensation, and color sensibility.     

Natural dye extraction from waste barks of Turkish red pine (Pinus brutia Ten.) timber and eco-friendly natural dyeing of various textile fibers

In this study, a natural dye extraction was carried out to isolate dyestuff extract powder from the waste barks of Turkish red pine (Pinus brutia Ten.) timber which is not a common natural dyestuff source. The natural dyestuff powder obtained was applied to cotton, flax, wool, silk, tencel, polyamide and acrylic fibers accompanied by simultaneous application of alum and natural oak ash mordants. Color properties were investigated including rub-, light- and wash-fastness performance. Differently dyed fiber samples exhibited slightly different shades of beige, brown and brownish-yellow depending on the mordant used and fiber type. Alum mordanted samples exhibited better color properties. The highest (63.4) and the second highest (45.3) f(k) color yield values were observed for alum mordanted silk and wool samples, respectively. Dyed fabrics showed excellent wash fastness, very low staining performance, and moderate light- and rub-fastness.     

Dyeing and DP treatment of sol-gel pre-treated cotton fabrics

Cotton samples were pre-treated with various sol solutions containing different alkoxysilanes (TEOS, GPTMS, APTES, and TESP-SA). The as-prepared cotton samples were dyed with 2 % owf Red and 4 % owf Blue. Furthermore, dyed cotton samples were after-treated with the alkoxysilanes. The alkoxysilane were also incorporated into the dyeing bath. The as- prepared cotton samples were subjected to a treatment with the non-formaldehyde durable press finishing agent BTCA in conjunction with the catalyst SHP. The textile materials were evaluated with respect to the colorimetric data (L*, a*, b*, ΔE*) and the color strength expressed in terms of K/S values. Tensile strength and dry crease recovery angles of the durable pressfinished samples were measured. The findings indicate that APTES and TESP-SA exert a significant influence on the color properties.     

Investigations on C-glycosyl flavonoids from Rhynchosia capitata,its antimicrobial and dyeing properties

Natural dyes extracted from a novel source Rhynchosia capitata (R. capitata) Heyne ex roth were applied to cotton fabric by applying traditional and pad dyeing processes using pre-, post- and simultaneous-mordanting techniques. Both dyeing processes were carried out in the presence of natural mordants: Myrobalan, Pomegranate rind, Rhizhophora mucronata fruits, Manjistha, and eco-friendly metallic mordants such as tannic acid, stannous chloride (SnCl₂), ferrous sulfate (FeSO₄), and copper sulfate (CuSO₄). The range of color developed on dyed materials was evaluated in terms of (L*, a*, b*, C*) CIELAB coordinates and dye absorption concentration on textile materials was studied by using K/S values. Natural mordant Rhizhopora mucronata fruits exhibited good absorption value. It was found that metallic mordants FeSO₄ and CuSO₄ exhibited higher K/S values than SnCl₂. For other mordants except FeSO₄ shade developed on cotton fabric varied from pale yellow to brown. The fastness properties ranged from good to excellent. High pressure thin layer chromatographic analysis for solvents of varying polarity has been investigated and maximum yield was obtained from 80 % aqueous ethanol fraction. Antimicrobial activity was carried out with the aid of two human pathogenic strains, Staphylococcus aureus and Klebsiella pneumonia and the cotton fabric dyed with plain extract of R. capitata shows good activity.     

Multifunctional polyester fabric using a multicomponent treatment

In this study, multifunctional polyester fabrics with the features of self-cleaning, water and stain repellency, and thermal stability were prepared utilizing a multicomponent system. To this end, both unmodified and alkaline-hydrolyzed modified fabrics were treated with nano TiO₂/citric or maleic acid/sodium hypophosphite/polysiloxane and triethanolamine via a pad-dry-cure method. Surface morphology and color variation of the samples were studied utilizing field emission scanning electron microscopy (FESEM) and CIE-Lab system, respectively. Also, energy-dispersive X-ray (EDX) analysis indicated the content of Ti, P and Si on the surface of fabrics. Thermal stability of the specimen was scrutinized through thermal gravimetric analysis (TGA) and char yield. Both hydrolysis treatment and silicone softener increased the uptake of the nanoparticles. Also, in a comparison between the utilized carboxylic acids, citric acid demonstrated superior features. Generally, the treated fabrics showed desirable self-cleaning and stain repellency with some enhanced thermal stability.     

Dyeing of wool with Marigold and its properties

This research work involves the dyeing of wool with Marigold as a source of yellow colour. To do this, wool yarns pre-treated with Alum as a colorless mordant, dyed with Marigold and then treated with different percentages of ammonia solutions. The chromaticity co-ordinates of samples measured in CIELAB system. TheL* values of all ammonia treated samples decreased and the values ofa*,b*,C* dependent on the ammonia solution. It can also indicate that the reflectance spectrum of treated samples decreases due to ammonia treatment. The rate of vertical wicking decreases on Marigold dyed treated with ammonia. Color hue of the Marigold dyed wool alters after washing with standard soap and ammonia after-treatment has no influence on washing fastness. The samples dyed with Marigold and after-treated with ammonia show a lower light fastness.     

Effect of carbon black nanoparticles on reflective behavior of printed cotton/nylon fabrics in visible/near infrared regions

Tuning the level of visible and near infrared (NIR) reflectance of textile surfaces is crucial for making them undetected in each environment. In this regard, samples of cotton/nylon fabrics were printed using a mixture of some special pigments and carbon black (CB) nanoparticles to produce brown, olive green and khaki shades which are present in concealment patterns of textiles employed in deserts. The effect of CB nanoparticles on Vis/NIR reflectance, air permeability, perspiration, light, wash fastnesses, and colorimetric values of each printed sample were evaluated. The presence of CB nanoparticles in printing formulations was found to cause significant decline in Near Infrared (NIR) reflectance of samples. The results showed that air permeability of samples printed containing CB nanoparticles are higher than samples printed with no CB particles. Absorbing phenomenon imposed by CB nanoparticles was fast against washing and perspiration, although printed samples indicated high to moderate light fastness. Furthermore, detectable change in visible appearance of the printed patterns was the main point of concern even at concentrations as low as 0.05 g/kg CB in printing formulation.     

Optimization and extraction of extra and intracellular color from <Emphasis Type="Italic">Penicillium minioluteum</Emphasis> for application on protein fibers

Precedence of microbial colorants can be seen in almost all the industrial sectors viz. food, textile, paper, agriculture, pharmaceutical, and cosmetics. These colorants are gaining popularity due to their salient advantages over synthetic and natural dyes. This study deals with the optimization and extraction of such colorants from Penicillium minioluteum for the purpose of dyeing different protein fibers. Penicillium minioluteum was cultured under different growth conditions to optimize the extracellular color production. The extracellular colorant grown under optimized fermentation conditions (medium-sabouraud; pH-5.6; temperature-15 °C; time-20 days; incubation-static) in 3000 ml haffkine flask showed maximum color or highest optical density of 1.014 at λ _max=490 nm. Later on, this colorant was extracted using nbutanol. The remaining mycelial mat obtained after filtration was extracted using different chemical and mechanical procedures to get the intracellular colorant. Highest O.D of 0.897 was recorded at λ _max=490 nm when desiccated powdered mycelial mat was extracted with methanol. Dyed silk and leather with the extracellular colorant showed color strength (K/S) as 3.88 and 3.81, respectively, whereas silk and leather dyed with the intracellular colorant showed K/S as 0.56 and 0.55, respectively. The color strength of extracellular dyed samples was found to be three times higher as compared to the samples dyed with the intracellular aqueous colorant of the same optical density. After dyeing, two different shades were obtained viz. deep red with the extracellular colorant and beige with the intracellular colorant on mulberry silk and wet blue goat nappa skin leather. Fastness towards rubbing was found to be good for both the samples. Wash fastness was excellent on silk. Fastness towards light was poor for both silk and leather. Furthermore, the color yield of the extracellular colorant (0.62 %) was found to be approximately five times more than the color yield of the intracellular colorant (0.14 %).     

A study on combining natural dyes and environmentally-friendly mordant to improve color strength and ultraviolet protection of textiles

In this study, natural dyes were extracted from five plants, namely diospyros kaki, dioscorea cirrhosa, millettia (jixueteng), ecliptae, and macrocarpa nucuma, using environmentally-friendly solvents, including ethanol and deionized (DI) water. A plant mordant, tannin extracted from Emblica officinalis G., and a metal mordant, copper sulfate, were used in the pre-dyeing process. Cotton and silk fabric samples were treated using the five natural dyes without and with mordanting for comparison on their color strength and characteristics as well as protection against ultraviolet radiation (UVR). Results revealed that Emblica officinalis G. had the highest total phenol content, followed by dioscorea cirrhosa. The presence of abundant phenolic groups in the natural dyes and mordant makes them effective coloration agents for fabrics. Cotton and silk fabrics dyed using ecliptae without pre-mordanting had the highest K/S values. Silk fabrics had higher K/S values than cotton fabrics, indicating greater color strength in pre-mordanted silk treated with DI water-extracted dyes. Natural mordant used before treatment with natural dyes contribute to significant enhancement in color strength, and Emblica officinalis G. alone could darken the color of cotton and silk fabrics dyed with plant pigment. Moreover, treatment with natural dyes after mordanting can increase ultraviolet protection factor (UPF) and the enhancement in UVR protection is greater and more significant in cotton fabrics than in silk fabrics, and in fabrics treated with DI water-extracted natural dyes than in those treated with ethanol-extracted ones. In conclusion, pre-dyeing with natural mordant followed by treatment with natural dyes extracted using environmentally-friendly solvents can enhance significantly K/S and UPF, offering directions for manufacturing textiles without environmental hazards but with good appearance and health benefits.     

Eco-dyeing and antimicrobial properties of chlorophyllin copper complex extracted from Sasa veitchii

Cotton fabrics were dyed with the natural chlorophyll derivates (chlorophyllin, Chlin) after treatment with and without chitosan. The water-soluble Chlin extracted from Sasa veitchii based on Japanese bamboo leaves were investigated in order to improve the textile coloration and antimicrobial activity. The antimicrobial activity of the dyed fabrics that had been pretreated with chitosan as a biomordant over a concentration range of 0∼0.7 % was tested against two common gram pathogens: Staphylococcus aureus and Klebsiella pneumoniae. The color depth as measured by the K/S value, the color difference and the colorfastness to washing and light were also evaluated. The fabrics treated with chitosan resulted in an increase in dye uptake in all cases compared with the corresponding untreated fabrics, and did not affect fastness of washing and light. The cotton fabrics dyed with mordant and CuSO₄ extracts appeared to have over 99.9 % of antimicrobial activity, while MeOH extracts showed 71.8 %.     

Immobilization of TiO2 nanoparticles on PET fabric modified with silane coupling agent by low temperature hydrothermal method

PET fabric was first modified with silane coupling agent KH-560, and then was loaded with a layer of nano-scaled TiO₂ particles using tetrabutyl titanate as precursor by low temperature hydrothermal method, followed by dyeing with Disperse Blue 56. The morphology, crystalline phase, chemical modification, thermal stability and optical property of PET fiber before and after treatments were studied by scanning electron microscope, X-ray diffraction, X-ray photoelectron spectroscopy, thermal gravimetric and diffuse reflectance spectrum techniques. The properties of tensile, air permeability, luster, ultraviolet (UV) protection, photocatalytic activity, K/S value and color fastness were also measured. It was found that compared with the TiO₂-coated fabric without modification with KH-560, the loading of TiO₂ nanoparticles on the surface of the TiO₂-coated fabric modified with KH-560 was obviously improved. The pure anatase TiO₂ nanoparticle was grafted onto the fiber surface. The onset decomposition temperature increased. The absorbing capability to ultraviolet radiation was enhanced. The properties of tensile, air permeability, luster, K/S value and color fastness changed slightly. The UV protection ability and photodegradation of methyl orange under UV illumination were enhanced to some extent.     

Meta-mordant Dyeing with <Emphasis Type="Italic">Camellia sinensis</Emphasis> (L.) O. Ktze var. <Emphasis Type="Italic">waldensae</Emphasis> (S.Y.Hu) Chang (Yellow-bud Tea) Extract for Wool Fabrics Treated by UV Radiation

The wool fabrics were treated by ultraviolet (UV) radiation and then dyed with Camellia sinensis (L.) O. Ktze var. waldensae (S.Y.Hu) Chang (yellow-bud tea) extract using meta-mordant dyeing method. The results indicated that the hydrophilicity of wool fabrics was improved after UV radiation treatment, which was conducive in improving color performance for the meta-mordant dyeing with yellow-bud tea extract of wool fabrics. The optimal dyeing process was that the powdered extract (5.0 % o.w.f) and the CuSO₄ (2.0 % o.w.f) were added to the dyeing liquor, the pH value was adjusted to 3.5-4.0 by HCOOH, the wool fabrics treated by UV radiation for 10 min and then were dyed at a bath ratio of 1:50 under 95 °C for 70 min. By means of three-factor quadratic current rotation revolving design (TQCRRD) method, the computation results of the mathematical equations and models indicated that UV radiation was the most important factor for meta-CuSO₄ dyeing with yellow-bud tea extract for wool fabrics.     

Synthesis and spectral characterization of novel azomethine disperse dyes derived from pyrazolone moiety and their dyeing performance on polyester fabrics

A series of new azomethine dyes based on pyrazolone system have been synthesized via different routes. The solvatochromism for the dyes was evaluated with respect to spectroscopic properties in various solvents. The dyes were applied as disperse dyes on polyester fabrics and gave shade poor to excellent light fastness, washing, perspiration, sublimation, and rubbing fastness properties. Also the position of color in CIELAB coordinates (L*, a*, b*) and K/S value were investigated.