Effect of reactive dyeing on the UV protection affected by knitted fabric made from different types of cotton fibre

In this study, 100% cotton knitted fabrics made from combed cotton and combed pima cotton were dyed with reactive dye, with different dye concentrations. Colour properties such as CIE L*a*b* values as well as dyeing uniformity of the dyed fabrics were measured. The relationships between colour properties and the ultraviolet protection afforded by cotton knitted fabrics were investigated. Experimental results revealed that dye concentration is the most important factor. In addition, only L* values have a direct mathematical relationship with the ultraviolet protection factor; a* and b* values and dyeing uniformity were not found to have a significant correlation with ultraviolet protection factor values. Meanwhile, knitted fabric made from combed cotton fibre has better ultraviolet protection performance than fabric made from combed pima cotton fibre.     

Electrostatic self‐assembly dyeing of cotton fabrics

A new approach to the dyeing of cotton fabrics using an electrostatic self‐assembly method was evaluated. Cotton fabrics were pretreated with 2,3‐epoxypropyltrimethylammonuium chloride and cationic charges were produced on the fabric surfaces. For the dyeing of cotton fabric, reactive and acid dyes were used. Oppositely charged anionic reactive/acid dyes and cationic poly(diallyldimethylammonium chloride) were alternately deposited on the surface of cationised cotton fabrics. Ten multilayer films of dye/poly(diallyldimethylammonium chloride) were deposited on the cotton fabric surfaces using a padder. The build‐up of the multilayer films and the level of colour strength (K/S) achieved are discussed. Samples of cotton fabrics were also dyed with the same dyes, but using the exhaust method, and both types of dyed samples were compared. The washing, rubbing and light fastness properties were evaluated for the dyed fabrics.     

Cetylpyridinium chloride cationic finishing improves the dyeing and antibacterial properties of madder dyed cotton

In this work, after cationic pretreatment of cotton fabric with cetylpyridinium chloride (CPC), the compound of citric acid (CA) and succinic acid (SUA) were used as crosslinking agents to dye cotton fabrics with natural madder dye to improve the dyeing and antibacterial properties and realise the multifunctional finishing of cotton fabric. The effects of mordant dyeing, CA + SUA crosslinked dyeing, and CPC/CA + SUA crosslinked dyeing on the microstructure and properties of cotton fabrics were compared. The dyeing by the three processes occurred primarily in the amorphous zone of the fibres, and all kept the original crystalline form of the cotton. CA + SUA crosslinked dyeing and CPC/CA + SUA crosslinked dyeing increased the thermal stability of the cotton fabric. CPC/CA + SUA crosslinked dyed cotton obtained excellent dyeing results with the colour depth value (K/S) of 12.3 and rubbing fastness and washing fastness of levels 4–5, and the levelness and dye permeability were acceptable. Furthermore, the antibacterial rate against Escherichia coli and Staphylococcus aureus reached 99.99%, and the ultraviolet protection factor (UPF) reached 50+. Moreover, the wrinkle recovery angle (WRA) increased by 55% compared with raw cotton. This showed that CPC/CA + SUA crosslinked dyed cotton had excellent antibacterial, anti-ultraviolet, and anti-wrinkle performances.     

Dyeing properties of textiles by Turkish hazelnut (Corylus colurna): leaves,coat, shell and dice

Turkey has a great number of hazelnut trees that possess nutritious components. However, only the inside part of the hazelnut is used as a nutrient, while the rest of it is waste. This study suggests that the waste parts of the Turkish hazelnut could be used as a natural dye for dyeing textile fabrics. The dyeing properties of the leaves, coat, shell and dice of the hazelnut were studied on wool, cotton and viscose fabric by using three different mordants: copper sulphate, iron sulphate and aluminium sulphate. The selected dyed fibre sample surfaces were observed using a scanning electron microscope. The colour strength (K/S), light, washing, rubbing, and perspiration fastness levels of the dyed fabrics were investigated. The experimental natural dyeing results indicate that waste hazelnut‐based products can be used as a natural dye for textile coloration.     

A method for dyeing cotton fabric with anthocyanin dyes extracted from mulberry (Morus rubra) fruits

For the first time, the natural anthocyanin dyes (mainly consisting of cyanidine 3‐glycoside) extracted from mulberry (Morus rubra) fruits has been successfully used to dye cotton fabric, with a dyeing property performance good enough for potential commercial applications. In this study, succinic acid was firstly incorporated into cotton fabrics by esterification to the hydroxyl groups of cellulose, forming an anionic site for the dyes. The performance of the modified material was characterised by Fourier transform infrared spectroscopy and tensile strength. Results showed that the tensile strength of cotton fabrics was mostly retained after modification. The anthocyanin extracts from mulberry fruits were used to study the dyeability of the control and modified cotton fabrics. Red and deep purple (aubergine) are two main shades of cotton fabrics dyed with mulberry fruit extracts. Most importantly, aubergine shade is rare in cotton fabrics dyed with natural dyes. Modification with succinic acid clearly increased the colour strength of the dyed cotton fabric. The colour strength of dyed cotton fabric was improved from 2.7 to 5.3 in the case of dyeing without mordants, and from 3.2 to 6.9 in the case of dyeing with tin mordanting. Meanwhile, the colour fastness was improved by 0.5–2 grades with increasing succinic acid concentration in the finish solution. The colour fastness to perspiration, crocking, light, and washing of fabric dyed with simultaneous tin mordanting and modified with 30 g l^?1 of succinic acid was found to be acceptable, with a grey scale grade of at least 3. As for home laundering, neutral soapy solution was more acceptable than alkaline soapy solution.     

The roles of polymer relaxation phenomena,aqueous dye solubility and the physical properties of water in the mechanism of adsorption of a disperse dye on poly(ethylene terephthalate) fibres: part 5 analysis of polymer relaxation phenomena for different polymers

The temperature dependent uptake of a commercial disperse dye on cotton and polyamide 66 fabrics at dyeing temperatures between 30°C and 130°C adhered to the Williams–Landel–Ferry equation, insofar as, very good correspondence was observed between plots of experimentally determined colour strength data points (log1/f_k) and the respective structural relaxation times of the cellulose and nylon 66 polymers (loga_T data points), as a function of the parameter (T − T_g). Adsorption of the dye on both types of fibre therefore concurs with the fundamental precept of the free volume model of dye diffusion. Comparison of the adherence of the uptake of the commercial dye on cotton and polyamide 66 fabrics with that secured on polyester fabric revealed that despite the major chemical and physical differences between the three types of fibre, the same dyeing mechanism likely applies to each fibre type. The marked temperature dependent uptake of the commercial grade disperse dye each of the three types of substrate is the consequence of two, different, but inherently interconnected, thermally activated phenomena, namely the relaxation times of the molecular rearrangements occurring within the respective cellulose, nylon 66 or poly(ethylene terephthalate) macromolecule, in which polymer glass transition assumes the principal role, and the aqueous solubility of the commercial grade disperse dye.     

Effects of atmospheric plasma treatment on the dyeability of cotton fabrics by acid dyes

Cotton fabrics were treated with air and argon atmospheric plasma for surface activation. Activated surfaces were grafted with two different amine compounds: ethylenediamine and triethylenetetramine. Pretreated cotton was dyed with acid dye and the effects of pretreatment on the colour strength, as well as the washing, rubbing and the light fastness of the dyeings, were investigated. Colour yield results showed that grafted ethylenediamine and triethylenetetramine enhance the dyeability of cotton fabric with acid dyes. Fourier transform infrared spectra confirmed the formed groups on the surface and scanning electron microscopy showed the etching effect of plasma.     

Improving the dyeability of wool by treatment with chitosan

A study of pretreatment of wool fabrics with chitosan by a pad-dry method has been carried out. The pretreatment effectively eliminates differences in dyeing behaviour between damaged and undamaged wool fibres, with an increase in the rate of dye uptake and the exhaustion of acid and reactive dyes. Penetration of the fibre by dyes has been followed using fluorescence microscopy and the role of the chitosan coating in the dyeing process clarified. Similar colour fastness properties were obtained on both untreated and chitosan-treated wool fabrics. The chitosan coating on wool fabrics has been examined by scanning electron microscopy. Evidence for the presence of chitosan was sought using a colorimetric method. It is believed that an approximately uniform and adherent chitosan sheath is formed on individual wool fibres.     

Novel hydrolysable azo disperse dyes based on N‐ester‐1,8‐naphthalimide: dyeing of polyester–cotton blends

The dyeing of polyester–cotton blends with new alkali‐hydrolysable azo disperse dyes based on N‐ester‐1,8‐naphthalimide was investigated. Polyester–cotton blend fabrics were dyed using both one‐ and two‐bath methods. Dyes 3 and 4 offered lower colour yield on polyester using the one‐bath method. For the rest of the dyes, employing either the one‐ or two‐bath method resulted in a similar colour yield on polyester fabric. The results for fastness properties and colour yield of the dyeings showed that the dyes were suitable for dyeing polyester–cotton blends using the one‐bath method. The kinetic study of hydrolysis of the dyes in alkali media obeyed the pseudo first‐order reaction rate.     

Adsorption and fixation behaviour of CI Reactive Red 195 on cotton woven fabric in a nonionic surfactant Triton X‐100 reverse micelle

To achieve the goals of saving water and being salt‐free in the coloration of cotton fabric with reactive dye, nonionic reverse micelles were prepared and optimised with a surfactant, Triton X‐100, n‐octanol and isooctane by injecting a small amount of CI Reactive Red 195 aqueous solution. The adsorption, diffusion and fixation of this dye on cotton fabric in Triton X‐100 reverse micelle and bulk water were then investigated. The equilibrium and kinetic data of the dye adsorption process were evaluated. The colour strength and fixation rate of cotton fabrics dyed in the micelle and in bulk water were also examined and compared. The results indicated that the amount of dye adsorbed increased with the increasing temperature and the initial dye concentration. The dye adsorption process could be described using the Langmuir isotherm and pseudo‐second‐order kinetic equations. It was found that CI Reactive Red 195 showed a stronger adsorption property on cotton fabric in Triton X‐100 reverse micelle than in bulk water without the addition of sodium chloride. Using Triton X‐100 reverse micelle as the dyeing medium offered the reactive dye better diffusion performance within the cotton fibre as compared with bulk water. Moreover, higher fixation of the dyes absorbed on the cotton fibre was achieved when the optimum concentration of sodium carbonate was used as the alkali agent in Triton X‐100 reverse micelle.     

Effect of cotton fabric pretreatment on drop spreading and colour performance of reactive dye inks

Ink dot distribution on cotton fabrics determines the colour performance of reactive dye inkjet printing, and ink drop spreading is one of the important factors influencing the ink dot distribution. In order to reveal the relationship between fabric pretreatment and ink drop spreading, two pieces of cotton fabric were pretreated respectively with sodium alginate and sodium alginate plus high fatty acid derivative solutions. Results indicate that the surface energy of the cotton fabrics was reduced from 73.79 to 69.45 and 58.49 mJ m^?2 after the pretreatment with sodium alginate and sodium alginate plus high fatty acid derivative respectively. Correspondingly, the spreading area of cyan ink drops on these fabrics was reduced from 104.9 to 92.5 and 72.3 mm². Furthermore, on the fabric treated with sodium alginate plus high fatty acid derivative, the strip‐like ink dots were narrow and short, which means the dye was concentrated in an area on the fabric surface. Colorimetric values of the inkjet‐printed fabrics demonstrated that the high fatty acid derivative would enhance the ability of sodium alginate to control ink droplet spreading, thereby improving the colour performance.     

Investigation and feed-forward neural network-based estimation of dyeing properties of air plasma treated wool fabric dyed with natural dye obtained from Hibiscus sabdariffa

In the colouring processes of textile products, more environmentally friendly chemicals and finishing methods should be used instead of conventional ones that harm the environment every day, so that alternative realistic ways to protect nature, both academically and industrially, could be possible. Due to some inconveniences caused by synthetic dyes that are widely used today, in this study, ultrasonic dyeing of wool fabric with Hibiscus sabdariffa was carried out after environmental-friendly air vacuum plasma application which increased the absorption of the dyes into the textile material. According to the performance results, colour strengths of the wool fabrics were increased significantly. Surface morphology analysis was carried out and etching effects of air vacuum plasma treatment were clearly seen on the micrographs of the treated wool fabrics. An environmental-friendly green process was achieved through this study and it was concluded that vacuum air plasma treatment could be an alternative green-process as a pretreatment to increase the dye up-take of natural dyeing treatment. Moreover, in this study, a feed-forward neural network (FFNN) model was presented and used for predicting the dyeing properties (L, a, b and K/S) of samples. The experimental results showed that the presented model achieves the regression values greater than 0.9 for all dyeing properties. Consequently, it was considered that the proposed FFNN was successfully modelled and could be efficiently utilised for dyeing characteristics of wool fabrics dyed with natural dye extracted from Hibiscus sabdariffa.     

Improving the environmental and economic aspects of cotton dyeing using a cationised cotton†

One approach to improve the affinity of anionic dyes for cotton is to add cationic dye sites to the fibre. The dyeing behaviour of cotton that had been rendered cationic by reaction with 2,3‐epoxypropyltrimethylammonium chloride was examined. Dye yields and fastness properties are reported for a number of direct, reactive and acid dyes with the modified fibre. Excellent dye yields and colour fastness properties were obtained without the use of electrolytes, multiple rinsings or fixation agents which are normally employed in cotton dyeing.     

Pretreatment of cotton fabrics with polyamino carboxylic acids for salt‐free dyeing of cotton with reactive dyes

In this study, polyamino carboxylic acids have been used to improve the dyeability of cotton in a salt‐free reactive dyeing process. These polyamino carboxylic acids were prepared by partial carboxylation of polyvinylamine. Cotton fabric was pretreated with polyamino carboxylic acids and dyed with reactive dyes. The colour strengths of the dyed fabrics were evaluated by measuring the K/S values. The fastness properties (washing, rubbing and light fastness) of the dyed cotton fabrics were also measured. The pretreatment of cotton with polyamino carboxylic acids creates positive charges on the fabric surface. In this way, salt‐free reactive dyeing of cotton or dyeing with only a small amount of electrolyte is possible.     

One‐step dyeing of polyethylene terephthalate fabric,combining pretreatment and dyeing using alkali‐stable disperse dyes

In the conventional dyeing process, polyester and its blended fabrics are usually dyed in a weak acidic medium. In order to reduce cost and improve production efficiency, a new dyeing method – one‐step dyeing of polyethylene terephthalate fabrics, combining pretreatment and dyeing in alkali conditions – was investigated. The alkali‐stable disperse dyes Red 900, Red 902, Yellow BROB and Blue 825 were used to dye polyethylene terephthalate fabrics. The dyeing properties of polyethylene terephthalate fabrics in the case of one‐step dyeing at various pH values or sodium hydroxide concentrations were discussed in terms of colour yield, colour parameters and fastness. The performance of one‐step dyeing using alkali‐stable disperse dyes was excellent. The dyed fabric had good fastness. Wet processing could be combined and shortened. One‐step dyeing of polyethylene terephthalate fabrics could reduce the consumption of water and energy and improve production efficiency. One‐step dyeing of polyethylene terephthalate has potential application in cleaner textile production.     

Using carbon black nanoparticles to dye the cationic‐modified cotton fabrics

Carbon black (CB) aqueous dispersion was prepared and used to dye the cationic‐modified cotton fabrics through exhaust dyeing process. The effects of CB concentration, CB nanoparticles size, dyeing bath pH, dyeing time and dyeing temperature were investigated. The color yields of dyed fabrics were evaluated on Kubelka‐Munk value K/S. The surface morphologies of cationic modified and nonmodified cotton fabrics were measured by video microscope. The fabrics presented 18.9 of the color yield with the dyeing conditions: the dyeing solution contained 2% o.w.f. CB and dyeing at 80°C for 30 min with pH 13 using a 50 : 1 liquor ratio. The images of the video microscope demonstrated a clear surface profile for the cationic‐modified cotton fabrics dyed with smaller CB particle size solutions. These results indicated that CB nanoparticles were suitable for dyeing the cotton fabrics. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

One‐bath union dyeing of a modified wool/acrylic blend with acid and reactive dyes

Pretreated wool/acrylic fibre was obtained by a facile amidoximation process. Fibre characterisation (nitrogen content, tensile strength, shrinkage, infrared spectra and X‐ray diffraction) proved the success of the pretreatment. Union dyeing of wool/acrylic fabrics with acid and reactive dyes, namely CI Acid Red 40, CI Acid Blue 25, CI Reactive Red 194 and CI Reactive Blue 25, was obtained using a one‐bath dyeing process. Different factors that may affect the dyeability of the blend fibre, such as dyebath pH, liquor ratio, temperature, time and dye concentration, were evaluated with respect to the dye exhaustion, fixation, colour strength, levelling and fastness properties. Excellent to good fastness was obtained for all samples, irrespective of the dye used. The result of the investigation offers a new viable method for union dyeing of wool/acrylic fibres in a one‐dyebath process.     

Low-temperature dyeing of meta-aramid fabrics pretreated with 2-phenoxyethanol

In this study, meta-aramid fibres were pretreated with 2-phenoxyethanol under different conditions to investigate the effect of 2-phenoxyethanol on the dyeing of aramid at low temperature (95 °C). Structural alteration of the pretreated fibres was reflected by thermogravimetry and Fourier transform infrared spectroscopy, indicating more H-bonds, lower crystallinity, and slightly lower thermal stability. The change in structure showed that 2-phenoxyethanol combined with the fibre macromolecules and resulted in swelling of the fibre. Creation of a biphasic system through the addition of 2-phenoxyethanol to the dyeing solution resulted in the cationic dye being partitioned more towards the 2-phenoxyethanol-rich phase than the aqueous phase. The cross-sections of the dyed fibre suggested that the meta-aramid fibre could be dyed more thoroughly with an appropriate concentration of 2-phenoxyethanol. The colour value of aramid fabric was tested by varying the concentration of 2-phenoxyethanol and the temperature of pretreatment, indicating a dramatic improvement in dyeing performance to aramid after 2-phenoxyethanol pretreatment. 2-Phenoxyethanol pretreatment and low-temperature dyeing can overcome the problems of chemical and energy waste while producing a satisfying colour.     

Ink‐jet printing process for lyocell and cotton fibres. Part 2: The relationship of colour strength and dye fixation to ink penetration

The colour appearance on ink‐jet printed textiles is influenced by a range of factors, including the chemical and physical nature of the fibre, dye–fibre affinity, pretreatment and fabric structure. Regression analyses were conducted to study the correlation between colour strength, fixation and ink penetration obtained by ink‐jet printing lyocell fibres (standard Tencel and Tencel A100) and cotton with an ink based on a monofunctional reactive red dye. The fixation was highest on Tencel A100, followed by standard Tencel and then cotton, while colour strength was highest on standard Tencel followed by cotton and Tencel A100. A linear relationship between colour strength and ink penetration was found with cotton, indicating greater dependence of depth of shade on ink penetration than on standard Tencel and Tencel A100 fabrics, where the interrelationships were more complex, but of low statistical significance. A schematic representation is proposed illustrating the mechanism of ink penetration into pretreated fibres, which provides a reasonable interpretation of the events occurring as dye penetrates into and fixes onto the fibres.     

One‐bath union dyeing of wool/polytrimethylene terephthalate blends†

The one‐bath dyeing of blends of polytrimethylene terephthalate (PTT) staple and wool has been investigated. The exhaustion of selected Terasil disperse dyes on PTT fibre and Lanasol reactive dyes on wool was measured as a function of temperature, together with the cross‐staining of the Terasil dyes on the wool component and the Lanasol dyes on PTT component. Most Terasil disperse dyes achieved satisfactory dye uptake on PTT at 110 °C, whereas on conventional polyester (polyethylene terephthalate) temperatures of up to 130 °C are required. An optimised union‐dyeing technique for wool/PTT blends was developed which minimised the staining of Terasil disperse dyes on wool and produced dyed goods with high levels of wet colour fastness. Carriers were not required to enhance the dyeability of PTT at low temperatures. The wool component appeared to be protected against damage at 110 °C by the reactive dyes. The results indicate the potential for blending PTT fibre and wool to produce fabrics that are easier to dye at lower temperatures than conventional wool/polyester blends.