Higher Dyeability Research Articles

Dyeing of some Egyptian cotton varieties using agricultural wastes (peanut outer skin)

Purpose Peanut skins are an agro-waste product with no commercial value. The purpose of this paper is to evaluate peanut skin as a natural dyestuff and to determine if this natural dye could be used in the dyeing of some Egyptian cotton cultivars. Design/methodology/approach The methodology consists of several steps; dye extraction procedure from peanut skin through aqueous extraction, then dyeing optimized using simultaneous mordanting using alum. Finally, dyed cotton has been subjected to different textile laboratory tests, for example, color measurements and mechanical properties. Color-fastness was determined on Egyptian cotton fabric. The peanut skin as a source of natural dye and the dyed cotton sample were characterized by fourier transform infrared spectroscopy (FTIR) analysis. Findings It was found that the natural dye extracted from peanut skin has an affinity for cotton samples and showed high dyeability with a unique color shade, good color strength and very good fastness. Originality/value The novelty of this paper is the extraction of color from the peanut's outer skin which is discarded as waste such as agro-waste of the agricultural process which can be used as a natural dye in the textile industry and applied to dyeing some Egyptian cotton fibers from different genotypes.

증류수와 에탄올로 추출한 어성초 염액의 색소 특성 및 염색성

The objective of this study was to determine characteristics of ethanol and distilled water extracts of Hottuynia codata and examine their dyeing properties by dyeing cotton and silk fabrics using different extraction and dyeing conditions. After measuring color fastness, antibacterial properties and deodorizing properties of dyed fabric, the following conclusions were obtained. Monosaccharides of phenols tannin and quercetin glycosides were extracted from Hottuynia codata. More flavonoid-based colorant was extracted with ethanol than with distilled water. Distilled water mainly extracted tannins. The ethanol extract showed the presence of chlorophyll. Cotton and silk fabrics showed YG color after they were dyed with ethanol extract. They showed Y color after they were dyed with distilled water extract. Dyeability of ethanol extract was higher than that of distilled water extract and that of silk fabric was greater than that of cotton fabric. As the concentration of the extract increased, the amount of dyeing increased. At dyeing temperature of 80°C with dyeing time of 60 minutes, a relatively high dyeability was found. Dyed fabrics showed high color fastness except for color fastness to sunlight. The fabric dyed with ethanol extract showed higher antibacterial activity and deodorization than that dyed with distilled water extract.

Application of smectite for textile dyeing and fastness improvement.

Three smectite-based pigments were prepared by the intercalation of cationic dyes utilizing the ion exchangeability of smectite, and the synthesis results were verified by X-ray diffraction and transmission electron microscopy. The study involved three fabric-dyeing methods: CD using only cationic dyes, SP using only smectite pigments, and ST using smectite post-treatment on fabrics colored with cationic dyes. For each method, dyeability, washing fastness, and colorfastness to artificial-light exposure were assessed by the absorption-to-scattering ratio (K/S), ΔK/S, and changes in color difference. Overall, CD showed high dyeability but low washing fastness and light fastness for all fabrics. In contrast, SP showed low dyeability and small changes in K/S and changes in color difference, representing washing fastness and light fastness, respectively. ST showed good dyeability, indicating that smectite post-treatment had improved both washing fastness and light fastness. Based on these findings, the improved fastness was attributed to dye release from the fabrics colored with the cationic dye during smectite post-treatment, as the dye simultaneously entered the interlayer space between the smectite layers, while coating the fabric surface with smectite.

Green Processing of Dyes: Influence on Physico- Mechanical Properties, Color Stability and Environment

The present article describes the role of dyes in enhancing the various properties of fibers along with their brief history and the recent methodologies used to minimize their negative impact on environmental safety. Since primitive age, natural dyes were used as coloring agents in textile industry. Later, in nineteenth century, synthetic dyes due to their high dyeability, varying shades ability, and comparatively low cost have replaced natural dyes. However, environmental concerns like water and marine pollutions forced the textile industry to develop new methodologies for the utilization of natural dyes with improved properties. Literature reveals that the use of new and advanced techniques have enhanced the dyeability, strength, softness, antimicrobial and other properties of textiles. These are mainly classified in to; a) the chemical modifications of natural dyes, and b) the surface modification of fabrics. In addition to these, the negative and positive impacts of these methods along with the future scope of research have also been discussed.

Acrylic/keratin composite of enhanced dyeability towards cationic and anionic dyes

Acrylic and keratin industrial wastes were dissolved, each separately, in their respective proper solvents. The soluble keratin was regenerated into powder and then mixed with the soluble acrylic to form an acrylic/keratin composite that was finally cast into film. The topography of the acrylic/keratin film was studied using scanning electron microscopy. The chemical composition of the obtained film was assigned using elemental analysis and infrared spectroscopy. The substantivity of the prepared acrylic/keratin film towards anionic (acid and reactive) and cationic (basic) dyes was studied. The obtained film exhibited high dyeability towards both acid and reactive dyes even at relatively low dyeing temperatures. Hydrazine hydrate was used to enhance the dyeability of the said film with acid and reactive dyes. Kinetic studies of the dyeing of the film with anionic dyes were also conducted.

Novel Method for Fast Bleaching of Cellulose Acetate Fabric by Using H2O2 Aided by Ultrasonic Waves

This research focuses on the use of ultrasonic waves to aid ultrasonic aided hydrogen peroxide (H2O2) bleaching (UAB) of cellulose acetate fabrics. UAB is studied under different conditions and based on the results obtained, the following conditions are established: H2O2 concentration, 10g/l; reaction temperature, 30°C; reaction time, 3 min; and pH, 9.0. The bleaching effect is expressed in terms of acetyl content, loss in fabric weight, whiteness index, roughness degree, tensile strength and elongation at break when the cellulose acetate fabrics are bleached per the UAB method as well as the conventional method. A comparison between the two methods with regards to these properties reveal the superiority of the UAB method with its novelty and fast inducing bleaching under the influence of cavitations and extra energy generated thereof; the cavitations are caused by the high frequency of the ultrasonic waves. Electron scanning microscopies of the UAB bleached fabric display a smooth and partially swollen surface morphology opposite those of conventionally bleached fabric in which the surfaces are irregular, rough and scratched bleached. In addition, UAB bleached fabric displays a significantly higher dyeability towards disperse dyes than the untreated fabric and fabric bleached by using the conventional method.

Eco‐friendly grafting of natural biopolymer chitosan onto acylated wool fabrics using ultrasonic and study its properties

AbstractThe use of ultrasonic for accelerating the chemical and physical processes of wool has gained high importance. This study aims to develop a method for reducing the energy and material consumption and decreasing fiber damage. Ultrasonic equipment (20 kHz) was used for grafting chitosan to wool fabric. Experiments were carried out under different times and chitosan concentration. The results showed using this technique decreases the time required for grafting chitosan onto wool which is less than the other procedures. Differential scanning calorimetry, Fourier transform infra‐red, and weight gain analyses provided evidence that chitosan was grafted onto the acylated wool through the formation of new covalent bonds in a short time. Scanning electron microscope was used to study the morphology of wool samples before and after modification. The dyeing of the chitosan grafted‐acylated wool fabrics indicates higher dye ability and lower shrinkage compared to the acylated and raw wool samples. The findings of this study support the potential of using ultrasonic as a friendly environment method for grafting chitosan onto wool with enhanced dye ability and reduced shrinkage properties. The grafted samples showed good antibacterial properties against Staphylococcus aureus as gram‐positive and Pseudomonas aeruginosa as gram negative bacteria. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

Environmentally friendly surface modification of silk fiber: Chitosan grafting and dyeing

In this paper, the surface modification of silk fiber using anhydrides to graft the polysaccharide chitosan and dyeing ability of the grafted silk were studied. Silk fiber was degummed and acylated with two anhydrides, succinic anhydride (SA) and phthalic anhydride (PA), in different solvents (dimethyl sulfoxide (DMSO) and N, N-dimethyl formamide (DMF)). The effects of anhydrides, solvents, anhydride concentration, liquor ratio (L:R) and reaction time on acylation of silk were studied. The polysaccharide chitosan was grafted to the acylated silk fiber and dyed by acid dye (Acid Black NB.B). The effects of pH, chitosan concentration, and reaction time on chitosan grafting of acylated silk were investigated. The physical properties show sensible changes regardless of weight gain. Scanning electron microscopy (SEM) analysis showed the presence of foreign materials firmly attached to the surface of silk. FTIR spectroscopy provided evidence that chitosan was grafted onto the acylated silk through the formation of new covalent bonds. The dyeing of the chitosan grafted-acylated silk fiber indicated the higher dye ability in comparison to the acylated and degummed silk samples. The mechanism of chitosan grafting over degummed silk through anhydride linkage was proposed. The findings of this research support the potential production of new environmentally friendly textile fibers. It is worthwhile to mention that the grafted samples have antibacterial potential due to the antibacterial property of chitosan molecules.

Physical and chemical modification of polyester fibres and filaments to improve the consumer properties of the finished articles

Different types of polyester fibres and filaments with valuable consumer properties are obtained by physical modification of PET. The fibres from chemically modified PET have high dyeability with disperse and cationic dyes, high thermal shrinkage, and low pilling in comparison to standard polyester. A polyester fibre with low combustibility (OI > 27) was made by incorporating fireproofing compounds in polycondensation of PET.

Wettability and Dyeability Modulation of Poly(ethylene terephthalate) Fibers through Cold SF6 Plasma Treatment

AbstractSummary: Surface modification induced on poly(ethylene terephthalate) (PET) fibers by cold SF6 plasma treatment has been investigated systematically as a function of plasma device parameters. The observed wettability modifications of fibers plasma‐treated under different operating conditions were correlated to their dyeability modifications and to the changes in surface chemical composition, determined by X‐ray Photoelectron Spectroscopy (XPS), and topography, investigated by atomic force microscopy (AFM). Optical emission spectra from the SF6 plasma at different pressures gave information on its content of fluorine atoms. A striking transition was observed between the increased hydrophilicity and high dyeability, imparted by plasma treatment at low pressure (<0.2 mbar), mainly as a consequence of surface etching and surface activation, and the increased hydrophobicity, imparted by plasma treatment in the higher pressure regime (0.2–0.4 mbar), consequent to extended surface fluorination.Water droplet adsorption time on PET fabrics, plasma‐treated at different pressures.imageWater droplet adsorption time on PET fabrics, plasma‐treated at different pressures.

Production and Use Of Polyester Fibres Today and Tomorrow

World production of polyester fibres and filaments in 2002 attained a record level: 20.4 million tons, including 11.8 million tons of complex filaments (+8%) and 8.6 million tons of fibres (+6%). The share of the former has increased at high rates in recent years and is now 58%, which is 16% higher than the share of fibres and twist. New kinds of fibres and filaments based on different polyesters are being manufactured on an industrial scale: liquid crystalline polymers — Vectran HS and Vectran M, poly(ethylene terephthalate) (industrial fibres), poly(butylene terephthalate) (fibres with high dyeability), and poly(trimethylene terephthalate) (fibres and filaments), as well as fibres with low combustibility, antibactericidal, conducting, and other fibres.

Polyester fibre with high dyeability and pilling

Polyester fibre based on poly(ethylene terephthalate) modified by addition of 3 wt. % sulfoisophthalic acid Na salt dimethyl ester, has high resistance to the pilling effect and elevated dyeability with disperse dyes. Sorption of the dye by the modified fibre at 100°C is several times higher (and in the case of a disperse dye, more than one order of magnitude higher) than sorption of dyes by mass-produced polyester fibre. The fastness of dyeing the modified and mass-produced fibres in different kinds of treatment is almost the same. The high sorption capacity of the modified fibre not only allows dyeing it with disperse dyes at normal pressure in a wide range of deep and medium shades, but also reducing the amount of unused dye in the baths and thus decreasing the effect on the environment.

Properties of Amphiphilic Calix(4)resorcinarenes Having Tetraalkyl Chains as Dyeing Auxiliaries.

Phosphate esters of calix_??_4_??_resorcinarenes having four alkyl chains (_??_4_??_Ar-Rn (P)) were prepared and examined as auxiliaries for dyeing of nylon 6 fiber with a disperse dye (KPLR). The dyeing with_??_4_??_Ar-Rn (P) was effective and the dye uptake was 40% more than that with a commercially available disperse agent (Disp-TL). The dyeing at 80°C and 95°C gave 10% and 25% higher dyeability respectively, as compared with the dye uptake using phosphate esters of monododecylresorcinol (M-R12 (P)). The maximal dye uptakes were obtained with 1-2g/dm3 of_??_4_??_Ar-Rn (P), and with 12g/dm3 of Disp-TL. respectively. The effect of_??_4_??_Ar-Rn (P) on the level dyeing was confirmed by the observation of the cross section of dyed fiber.

The effect of heat setting on the dyeability of differentially dyeable polyester fibres

Apparent diffusion coefficients of two disperse dyes for so‐called easily dyeable/cationic‐dyeable polyester (ED‐CDPET) and cationic‐dyeable polyester (CDPET) fibres of identical linear density and sulphonic acid group content have been calculated. It was found that the diffusion coefficients of dyes for ED‐CDPET were far greater than those of dyes for CDPET. The dyeability at the boil without carrier, using disperse and cationic dyes on various ED‐CDPET and CDPET fibres, has been studied. ED‐CDPET was found to have higher dyeability at all levels of heat setting (irrespective of the dye used). The finest ED‐CDPET fibres showed maximum dye uptake as a result of increased surface area. Heat setting in the taut condition reduced dye uptake.

Interactions of Nonaqueous Solvents with Textile Fibers

An investigation of the effects of prior heat treatments on the stabilization of the polyester structure towards subsequent treatments with dimethylformamide (DMF) has been carried out. The results indicate that a DMF treatment at 140°C can overcome changes in the polyester structure produced by prior heat treatment up to a temperature of about 180°C. Void formation and accompanying high dye uptake under atmospheric dyeing conditions are observed. Heat treatments around 200°C, however, stabilize the fiber structure, and subsequent solvent treatments do not produce irreversible swelling and void formation. A further increase in the heat-treatment temperature again permits void formation and high dye-uptake values to occur. A close correlation between dyeability and void volume calculated from density data is observed. A DMF treatment of a false-twist-set textured yarn leads to void formation and high dyeability, even though the heater temperatures used in the texturing process are near the critical temperature range at which stabilization to sub sequent solvent treatments has been observed. Evidence is presented suggesting that the yarns do not actually experience the temperature of the heaters but rather a significantly lower temperature.