Dye Fixation Rate Research Articles

Modification of ramie fibre with a mixture of NaOH solution and iso-propanol solvent for enhancing its dyeing performance

Deep shade dyeing of ramie fibre is challenging due to its high degree of polymerisation, orientation, and crystallinity. The present work involved pre-treating ramie fibre with a solution containing a mixture of NaOH and alcohol in order to improve its dyeing ability. Based on the first screening results, it has been shown that iso-propanol is the optimal alcohol solvent for modifying ramie fibres with a mixture of NaOH solution, resulting in greater levels of dye exhaustion (E%), dye fixation rate (F%), total dye fixation efficiency (T%), and K/S values. Subsequently, the orthogonal array experimental technique (L16) was utilised to optimise the treatment conditions, and it was determined at a temperature of 25 °C, using a NaOH solution with a concentration of 140 g/L, a liquid ratio of 1:2 for the volume ratio of NaOH solution to iso-propanol solvent, and a treating period of 3 min. The treated samples were subjected to a range of analytical techniques, including XRD, FTIR, TGA, and SEM; these analyses conclusively verified that the samples' properties were altered due to the optimal combination treatment. The combination solution-treated samples had significantly higher barium values compared to the other samples, suggesting an ideal mercerisation treatment. The colourfastness to washing values exhibited satisfactory results for the treated samples. Besides, a handle assessment of raw ramie fabric and treated ramie fabric was conducted to enhance the practical application feasibility.

Improving the dyeability of ramie fibre by sequential alkaline and alcohol pretreatments

The high crystallinity of ramie fibre poses challenges in achieving optimal dyeing performance, such as reduced dye exhaustion. To enhance the dyeing capabilities of ramie fibre, several alterations were experimented with, such as caustic mercerization using a NaOH solution. However, because of the high NaOH concentration, removing the NaOH residue from inside the fibre becomes challenging. Herein, the present research aims to enhance the dyeing efficiency of ramie fibre by using sequential alkaline and alcohol pretreatment methods to reduce NaOH usage, accordingly relieving the wash process stress. The preliminary screening findings have revealed that iso-butanol is the most suitable alcohol solvent for modifying ramie fibres after treating it with NaOH solution since it leads to higher dye exhaustion (E%, 95.7%), dye fixation rate (F%, 88.2%), total dye fixation efficiency (T%, 84.4%), and K/S values (41.4). After that, the orthogonal array experimental scheme (L16) was applied to optimize dyeing performance. The NaOH usage was decreased to 160 g/L, the treating time was reduced to 3 min, and the dyeing performance of ramie fibre treated under the optimum conditions was better than that of a caustically mercerized one. It was determined that the NaOH concentration factor had the most contribution, accounting for 75.34% of the observed effects. The NaOH solution temperature factor followed closely behind, contributing 22.69%. Additionally, using analytical methods such as XRD, FTIR, TG, and SEM confirmed that the sequential treatment with the optimum conditions altered the structural behaviour of the original ramie fibre, which performances were similar to the mercerized ramie fibre. The barium value of sequentially iso butanol solvent treated fibre showed a greater level (213) compared to caustic mercerized fibre (179), indicating a significant advantage of mercerization performance was achieved. This advantage may be linked to improved colourfastness and handling qualities. Furthermore, the breaking force of both ramie fabrics was increased after the alkaline treatment and the sequential alkaline and iso-butanol treatment.

Low temperature non-aqueous dyeing of wool fiber with reactive dyes: A sustainable and eco-friendly method

Conventional wool dyeing usually performed at a boiling point, often destroys the wool structure, consumes plenty energy and water. Aiming at realizing the sustainable cleaning coloration of wool dyeing and keeping the excellent natural quality of wool fiber, a green dyeing technology, non-aqueous dyeing, has been successfully applied. The effect of acid-pretreatment on the reactive dye adsorption behaviors was explored and optimized the dyeing parameters by the design of experiments as well as a single factor screening way. The results demonstrate that acid-pretreatment improved the dye exhaustion rate to 99.79 % effectively by lowering the pH value of wool fiber and increased the dye fixation rate from 75.33 % to 86.93 % by enlarging the dyeing channel. Additionally, the factors that affected wool dyeing were analyzed, approving additional acetic acid had the most significant effect on the wool dyeing. The optimal wool dyeing condition included 1 % on the weight of fiber (o.w.f) acetic acid indicating low-temperature wool dyeing was achieved by this non-aqueous dyeing system at 85 °C for 60min. Furthermore, a higher color depth, constant mechanical properties, good rubbing fastness, and soaping fastness were obtained by this dyeing method. Compared with conventional dyeing, 24.28% energy consumption, 32.50% water usage, and 31.36% wastewater were reduced by this dyeing method. Therefore, sustainable non-aqueous dyeing technology is eco-friendly and has the potential to protect the wool structure from being damaged in the dyeing process.

Green penetration dyeing of wool yarn with natural dye mixtures in D5 medium

This investigation reported a mixture of natural dyes by employing the D5 solvent as a green penetration dyeing system for wool fiber. The ideal dyeing conditions were determined by conducting an in-depth analysis of the following variables: AEO-3 concentration, aqueous pick-up rate, solution pH, dyeing time, temperature, dye mass, and dye fixation percentage. Tensile strength and elongation were measured to learn more about the mechanical characteristics of the wool yarn after it was dyed in D5 solvent and water. The suggested dyeing parameters for wool yarn are 2% of AEO-3, 400% of the wool aqueous pick-up rate at pH 3, 90 °C temperature, and 90-min duration. This was determined by calculating the K/S value and the dye fixing rate. A washfastness of 4–5 on the fading scale and a stainfastness of 5 across the board were acquired. MR and GB dyes obtained a high dye fixation rate within 90–100%; however, GY dye achieved about 50% dye fixation rate. X-ray diffraction (XRD) patterns and thermogravimetric analysis (TGA) verified that the original and dyed wool fiber showed no change in interplanar distance in crystallinity and stable thermal tendency due to the dyeing process. The morphology of the wool's surface was not altered throughout the dyeing process, and the colors were spread uniformly over the fiber in SEM pictures and cross-sections. Finally, natural dyes in a D5 solvent media may be used to produce a ternary color, laying the groundwork for natural dyes to be further industrialized.

Hot pad–batch dyeing of cotton fabrics using reactive blue-vinyl sulfone dye

Cold pad–batch dyeing of reactive dyes is low energy consumption and a clean dyeing technique. However, the room dyeing temperature requires strongly active base reactive dyes for dye fixation, bringing about the limitation of dye adaptability. Here, we propose a new technology of hot pad–batch dyeing that has the advantages of higher dye fixation and excellent color fastness. Three blue reactive dyers (C.I. Reactive Blue 19, C.I. Reactive Blue 21, C.I. Reactive Blue 203) that contain β-sulfate ethyl sulfone were used to increase the dye fixation of reactive dyes with cotton fibers. The effects of alkali concentration, dyeing temperature, batching time, and salt concentration on the dyeing performance of cotton fabrics were studied. The effects of post-treatment (soaping and fixation) on the K/ S values and color fastness were also investigated. The study showed that the dye fixation rate of the three reactive blue dyes was higher than 87%, and the rubbing and washing color fastness was more than grade 3–4 in the process of hot pad–batch dyeing of cotton fabrics. Furthermore, the dyed cotton fiber was fixed with a fixing agent (polyurethane (PU) and a mixture of PU and an aziridine crosslinker), and the color fastness reached not less than grade 4. Compared with cold pad–batch dyeing, hot pad–batch dyeing has the advantages of higher dye fixation and excellent color fastness for the three reactive blue dyes. Therefore, the dyeing performance of β-sulfate ethyl sulfone types of blue reactive dyes using hot pad–batch dyeing can effectively reduce the burden of post-treatment and the discharge of dyeing wastewater, and has a good application prospect in the dyeing of cotton fabrics.

Sustainable traditional grass cloth fiber dyeing using the Taguchi L16 (4^4) orthogonal design

For many centuries, traditional grass cloth has been used as an important raw material for home textiles in China, but its market can be expanded by incorporating color. Reactive Red 2 (R2), Reactive Blue 194 (B194), and Reactive Orange 5 (O5) were used in this work to explore the dyeing behavior of sustainable traditional grass fiber using industrial dyeing methods. Initially, an L16 (4^4) orthogonal design was schematically applied to carry out the dyeing process and it was determined that the total dye fixation rate (T%) of B194 dye was the best among the three dyes. Accordingly, a statistical Taguchi technique was analyzed on a larger scale to optimize the dyeing process parameters (salt concentration, fixation time, fixation temperature, and solution pH) of B194, in which solution pH was found to be the most influential factor in achieving the highest T%. This phenomenon was also verified using analysis of variance (ANOVA), where the solution pH was found to be the biggest contributor (50%) and statistically significant (p < 0.05). Finally, confirmation tests were conducted under optimized conditions and a higher T% (53.18%) was determined compared to initial conditions (48.40%). Later, Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM) were used to analyze the structural characteristics and found that grass cloth was chemically stable, yet gummy materials were still observed on their surface, which was also confirmed from digital photographs. Generally, the color coordinates and fastness properties were also satisfactory.

A Synergism of Eco-Friendly Dyeing of Cotton Fabric and Therapeutic Benefits of Bixa Orellana Seed

Background and objectives: The present research is aimed to study the eco-friendly nature and therapeutic application of the natural dye from the seed extract of Bixa orellana for maximizing the benefits of cotton fabric. Materials and methods: A natural dye was extracted from Bixa orellana seeds by hot water and ethanolic extraction method. This dye was examined for its ability with pre-mordanting and post-mordanting of cotton fabrics with ferrous sulphate, hydrated double sulphate and tamarind seed powder in order to improve the aesthetics and natural color shades on cotton fabrics. Furthermore, the dyed cotton fabric was used to analyze the antibacterial efficacy of cotton fabric against bacterial culture such as Bacillus cereus, Escherichia coli, Proteus mirabilis, Salmonella typhi and Klebsiella pneumoniae. Results: Our results suggest that pre- mordanting of cotton fabric with ferrous sulphate, alum and tamarind seed shows good dye fixation rate and stronger color than post-mordanting. Dyeing of cotton fabric with the ethanol extract of Bixa orellana seeds gave excellent and beautiful shades than the ones extracted with hot water. Furthermore, cotton fabric dyed with ethanol extracted was found significantly active against human pathogens compared to cloth dyed with hot water extract. The results evidenced that cotton knitted fabrics showed an increase in dye uptake with natural mordant and strength with a considerable reduction in antimicrobial activity. Conclusion: This research adumbrated developing a greener technology to cabalistic use of Bixa orellana seed extract applied on cotton cloths for coloring and in future find commercial use as a functional finishing agent (for newborns, clothing for burns, injured soldiers and hospitals) for health protection with semi-durable therapeutic properties.

An efficient dye-fixation technique with reactive dye for a wash-free process of silk fabrics without water discharge

Coloring textiles with less or without water discharge for sustainable and cleaner production has been a hot topic for a long time due to increasing social, environmental and consumer requirements. In this paper, a new and efficient dye-fixation technique with reactive dye for a wash-free process of silk fabrics without water discharge is presented. Here, decamethylcyclopentasiloxane is employed as the dyeing medium, Reactive Black 5 as the selected dye and sodium carbonate as the alkali. The results show that the dye-fixation rate is higher than 90% and the dyed silk fabrics have good color strength, tensile properties, hand values (including stiffness, softness and smoothness), washing fastness and wet rubbing fastness when adding proper alkali into the dye solution. A probable mechanism was proposed.

Combination of Pre- and Post-Mercerization Processes for Cotton Fabric.

The dyeing process commonly deteriorates the luster of pre-mercerized cotton fabric, so post-mercerization processes are regularly applied to compensate for this. Herein, the influence of combining pre-mercerization with CS (caustic solution) or LA (liquid ammonia) and post-mercerization with CS or LA on the morphological structure, dyeing performance, tensile strength, and stiffness of woven cotton fabric was investigated. The crystallinity index values greatly decreased from 73.12 to 51.25, 58.73, 38.42, and 40.90% after the combined mercerization processes of LA–LA, CS–CS, LA–CS, and CS–LA, respectively. Additionally, the CS–LA- and LA–CS-treated samples exhibited a mixture of cellulose II and cellulose III allomorphs. The combined mercerization processing of cotton fabric resulted in slightly worse thermal stability. The LA and CS pre-mercerization processes increased the dye exhaustion, although the former decreased the dye fixation rate while the latter increased it by 4% for both dyes. The color strength of the dyed cotton fabric increased after both post-mercerization processes. Moreover, the fabric stiffness and mechanical properties showed an increasing trend due to the combined mercerization efforts.

Combination of wet fixation and drying treatments to improve dye fixation onto spray-dyed cotton fabric

The conventional dyeing process requires a substantial amount of auxiliaries and water, which leaches hazardous colored effluents to the environment. Herein, a newly developed sustainable spray dyeing system has been proposed for cotton fabric in the presence of reactive dyes, which has the potential to minimize the textile dyeing industries environmental impact in terms of water consumption and save significant energy. The results suggest that fresh dye solution can be mixed with an alkali solution before spray dyeing to avoid the reactive dye hydrolysis phenomenon. After that, drying at 60–100 °C, wet fixation treating for 1–6 min, and combined treatments (wet fixation + drying) were sequentially investigated and then dye fixation percentages were around 63–65%, 52–70%, and above 80%, respectively. Following this, fixation conditions were optimized using L16 orthogonal designs, including wet fixation time, temperature, dye concentration, and pH with four levels where the “larger-the-better” function was selected to maximize the dye fixation rate. Additionally, the color uniformity and wash and rubbing fastnesses were at an acceptable level when both treatments were applied. Finally, the dyes were hydrolyzed after wet fixation, and the hydrolysis percentages were enhanced after the drying process.

Study on Dyeing Process of Bamboo Pulp Fiber Fabric with Pomegranate-peel Dye

The pomegranate-peel dye was extracted by boiling in this paper. Through orthogonal experiments, using dye fixation rate as an indicator, it has studied the best dyeing process of pomegranate-peel dye for dyeing bamboo pulp fibers with direct dyeing and same-bath mordant dyeing methods. The dyeing process parameter are optimized through orthogonal experiments as follows: (1)with direct dyeing method, when dyeing 30minutes or 50minutes, the optimal process parameters are dyeing concentration X, dyeing temperature 80°C, and dyeing PH value 8; when dyeing 70minutes, the optimal process parameters are dyeing concentration 2/3X, dyeing temperature 80°C, and dyeing PH value 9.(2) with same-bath mordant dyeing method, when dyeing 30minutes, the optimal process parameters are dyeing concentration X, dyeing temperature 80°C, and dyeing PH value8; when dyeing 50minutes, the optimal process parameters are dyeing concentration 2/3X, dyeing temperature 60°C, and dyeing PH value7; when dyeing 70minutes, the optimal process parameters are dyeing concentration X, dyeing temperature 60°C, and dyeing PH value9. It is concluded that the bamboo pulp fiber dyed with pomegranate-peel dye has good dyeing performance, which meets the color fastness requirements of fabrics.

Effluent-free deep dyeing of cotton fabric with cacao husk extracts using the Taguchi optimization method

Textile dyehouses are under scrutiny because they discharge colored and hazardous effluents to waterways. There is a need to develop an alternative dyeing system that does not produce any hazardous effluent. The waterless dyeing method could be a viable eco-friendly alternative to the traditional aqueous dyeing method. In this work, cacao husk extracts were used as a natural dye in the decamethylcyclopentasiloxane (D5) medium for the dyeing of cotton fabric, and subsequently, the dyed cotton was treated by a fixation treatment with a cationic dye-fixing agent in the D5 medium. The cotton fabric dyed with cacao husk extracts exhaustion in the waterless D5 medium exhibited better exhaustion, fixation rate, color strength (K/S), and colorfastness to washing and rubbing compared to the fabric dyed with the same extracts using the conventional aqueous dyeing and dye-fixing methods. The dye exhaustion percentage and the dye fixation rate were 95.6% and 94.8% in the D5 medium respectively, which is significantly higher in comparison to a 48.2% dye exhaustion percentage and a 35.3% dye fixation rate in the conventional water medium. An orthogonal array design (L9) was adopted to optimize the dyeing conditions with respect to exhaustion percentage. The results indicated that the dyebath temperature was the most important factor for achieving the optimal dye exhaustion, and dyeing time also showed considerable effects. Linear regression was used to predict the exhaustion percentage, and the resulting p value of 0.000 demonstrated that a strong coefficient was proven among all selected factors. This study has demonstrated that dyeing of cotton fabric with cacao husk extracts in the D5 dyeing system can be a viable method for the textile industry with minimal environmental pollution.

Improved reactive dye fixation on ramie fiber in liquid ammonia and optimization of fixation parameters using the Taguchi approach

Dyeing in liquid ammonia has the advantage of penetrating the reactive dye molecules inside the fiber structure by modifying the cellulose supramolecular from a crystalline to amorphous form. However, the dye fixation rate of the baking treatment is unsatisfactory (29.45%). In this study, ramie yarn hanks were dyed in liquid ammonia, and cationic fixation auxiliary silicone micro-emulsion was used to fix the dye molecules in the fibers to improve the dye fixation rate and fastness properties. The fixation parameters were optimized using the Taguchi approach. The optimum conditions of the cationic fixation auxiliary mass, fixation time, and water content with four levels on the fixation rate were investigated using an L16 orthogonal array. The larger-the-better signal-to-noise ratio was applied to maximize the responses of the parameters. The main effect and interaction plot of several factors were analyzed, with results suggesting that the mass of the cationic fixation auxiliary is the most influential parameter for the fixation of the reactive dye (P < 0.05). A fixation rate for the reactive dye of 52.82% ± 0.5% was observed under the optimal conditions. The color uniformity, wash fastness and rubbing fastness of the dyed sample treated by the cationic fixation auxiliary silicone micro-emulsion were exceptional.

Effects of Viscosity and Surface Tension of a Reactive Dye Ink on Droplet Formation

In textile inkjet printing, understanding the effect of viscosity and surface tension of a reactive dye ink on droplet formation is of great significance. As an organic ecofriendly solvent, polyethylene glycol with a molecular weight of -400 g/mol (PEG400) was used to prepare reactive dye inks with or without Surfynol 465 (S465) to explain separately how viscosity and surface tension affect the droplet formation of a reactive dye ink. The intermolecular interactions in the ink and physical properties of the ink were investigated by measuring the visible absorption spectra, hydrodynamic radius, viscosity, and surface tension. Droplet formation under a single variable influence of viscosity or surface tension was observed by taking photographs using a high-speed camera. Results show that a high ink viscosity condition generates no satellite droplet formation and a slower droplet velocity, and a higher surface tension tends to cause ligament rupture from the nozzle tip and the droplet. Moreover, a twill cotton fabric printed using the PEG-S465-dye ink at a 30% PEG400 concentration showed higher ink penetration, dye fixation rate, ideal color strength, and rubbing fastness.

Study the dyeing behavior of wool fabric using henna extract in decamethyl cyclopentasiloxane (D5) medium

In this study, an eco-friendly dyeing method of wool fabric was adopted using natural dye extracted from henna leaves in the Decamethyl Cyclopentasiloxane (D5) medium. D5 was used to reduce the consumption of the high amount of water and salt needed in traditional dyeing. Wool fabric dyed with different amounts of Henna extract/Decamethyl Cyclopentasiloxane at different dyeing temperatures (40 and Scanning electron microscopy (SEM) and Energy-dispersive X-ray spectroscopy (EDX) were used to study the effect of the D5 on the morphology and elemental composition of the fiber surface. The dyeing and fastness properties of the dyed fabric were also investigated. The results showed that the dye uptake, fixation rate, and color strength of the samples dyed in this system were higher than water-based dyed samples. The dye uptake rates of the samples dyed in this system were 77–83% as compared with 64–71% for the water-based dyed samples. SEM and EDX results illustrated that dyeing in the D5 medium did not show any adverse effect on the morphology and elemental composition of the fiber surface.

Green synthesis of reactive dye for ink‐jet printing

AbstractChloropyrimidine‐based reactive dyes are reported as well suited to textile printing; however, nucleophilic aromatic substitution of chloropyrimidines with amino‐containing chromophores is slow and often suffers from poor yields. In this study, a novel and simple method was developed for the synthesis of chloropyrimidine‐based reactive dye under microwave irradiation. In addition, the dye was also synthesised by conventional heating for comparison, which took both the reaction time and yield into account. The progress of the synthesis reactions concerned were monitored using capillary electrophoresis and the purity of the dye obtained was assessed by thin‐layer chromatography. The structure of the synthesised trichloropyrimidine dye was confirmed by Fourier Transform–infrared spectroscopy and elemental analysis. It was found that the reaction rate of the nucleophilic aromatic substitution carried out under microwave irradiation was 4‐fold faster than that carried out under conventional heating, although the enhancement in product yield was modest. These results suggest that microwave irradiation is an effective technique for the synthesis of chloropyrimidine‐based reactive dyes. The synthesised chloropyrimidine dye was formulated into an ink and applied onto a wool fabric by ink‐jet printing. The printed fabrics were steamed at 102°C for 5‐25 minutes at 5‐minute intervals. Good K/S and rate of dye fixation were obtained, both of which improved with increasing steaming time. The prints obtained exhibited reasonably good light and wash fastness properties.

Effective Cross-linking Dyeing Method for Jute Fabric with Reactive Dyes

With a view to develop an effective dyeing method for jute fabric, jute fabric known as Carpet Backing Cloth (CBC), made from jute fiber, was first desized, scoured, and bleached with hydrogen peroxide. Simultaneous dyeing and finishing methods were carried out using various reactive dyes with some cross-linking agents like Fixapret CPN, Fixapret ECOs of BASF, and Indosol E-50 Powder (Sandoz) along with some catalysts (MgCl2, 6H2O) and softening agent. Three types of cross-linking methods such as dry, moist, and wet were employed. The cross-linking method was optimized by treatment of bleached CBC with different concentrations of cross-linking agents and catalysts applying pad-dry-cure method at different temperatures. Significant improvement was found in dye fixation rate, dye fastness (washing, rubbing, light and perspiration) properties, and tensile strength of cross-linked dyed jute fabric. Regarding all dyeing and physical properties, Indosol E-50 powder along with various reactive dyes achieved highly satisfactory results. Fixapret CPN may also be comparable to Indosol E-50 powder.

Optimization of the cationizing condition in salt‐free reactive dyeing of cotton fabric with the pad‐irradiate‐pad‐steam process using response surface methodology

AbstractResponse surface methodology is widely used in the optimization of dyeing conditions. Herein, the color strength and dye fixation rate of the cotton fabric dyed by pad‐irradiate‐pad‐steam (PIPS) process were determined and compared to by conventional pad‐dry‐pad‐steam (PDPS) process. Then the response surface methodology and central composite design were used to optimize the cationizing conditions during the pad‐irradiation step of the process to obtain high color strength during the subsequent salt‐free reactive dyeing of the cotton fabric via a pad‐steam process. The obtained experimental data were fitted to the second‐order polynomial equation, and response surface plots and contour plots were used to identify the optimal cationizing condition, the 3‐chloro−2‐hydroxypropyltrimethylammonium chloride concentration of 104 g/L, the microwave irradiation power of 537 W, the treatment time of 6 min, and the molar ratio of sodium hydroxide to 3‐chloro‐2‐hydroxypropyltrimethylammonium chloride of 1.02. The results showed that the experimental color strength of the cotton fabrics was in close agreement with the value predicted by the model and the optimal cationizing condition was obtained precisely.

Effect of Breed and Age on the Dye Fixation and Optimization of Wool Dyeing with Reactive Dye

The present paper investigates the effects of breed and age on the dye fixation on wool using a reactive dye. It also examines the optimization of the dyeing process realized using the response surface methodology. The dyeing step was carried out on raw wool using the bichromatic blue dye reagent Cibacron P-3R (C.I. Reactive Blue 49). The factors affecting the dyeing process, such as ammonia concentration, temperature, and the duration of the dyeing time, were studied using the response surface methodology. The performance of this dyeing process was evaluated by measuring the color yield (the dye fixation). The results have shown that the age and the breed of sheep have a significant effect (P <0.05 %) on the dye fixation rate. This can be attributed to the differences in the amino acids of wool. Additionally, it has been found that the youngest wool and the Sicilo-Sarde breed always yielded the best dye fixation while the oldest wool and the Fine Queue of west breed (QF) have the lowest dye fixation. Using the response surface methodology, this research has proved that the best dyeing quality for the QF is obtained by using an amount of ammonia of 20 ml, a dyeing duration of about 60 min, and a dyeing temperature of about 100 °C.

High Dye Fixation Pad-Steam Dyeing of Cotton Fabrics with Reactive Dyes Based on Hydrophobic Effect

ABSTRACTTo enhance the dye fixation of pad-steam dyeing with reactive dyes, we used five kinds of dyes and water–ethanol dyeing medium to investigate the hydrophobic effect in dyeing process. The results indicated that the higher the molecule weight per water soluble group, i.e. the stronger dye hydrophobicity, the higher the dye fixation rate. When dyed with hydrophobic dye, both the alkali and steaming time can be reduced to realize the saving of chemicals and energy. For the more hydrophobic C.I. Reactive Orange 16 (RO16), the appropriate sodium carbonate concentration is 20 g/L, which is 10 g/L lower than the 30 g/L of C.I. Reactive Violet 5 (RV5). Similarly, RO16 just needed 2 min of steaming time to obtain the maximum K/S value, while RV5 needed 3 min. Enhancing the hydrophobicity of dyeing medium can also increase the dye fixation rates and K/S values. The K/S values and fixation rates of fabrics dyed with RV5 increased up mostly by 31.2% and 14% via using ethanol instead of 32 vol.% water in dyeing medium, respectively. All the dyed fabrics exhibit good color fastness.