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Thermodynamic adsorption parameters of 1,4-diaminoanthraquinone on polyethylene terephthalate (PET) were determined using several alkane media ranging from pentane to decane. In the range from pentane to decane, as the number of carbon atoms in the alkane decreased, the standard affinity (−Δ μ 0 ) increased. From the results of the enthalpy change (Δ H 0 ) and the entropy change (Δ S 0 ), it is found that when adsorbed in the longer chain of alkane medium than in the shorter one, the dye molecules were more strongly embedded within the PET substrate. The diffusion coefficient ( D T ) of the dye decreased and the activation energy ( E D ) increased with increasing number of carbon atoms in the alkane.

Dyeing properties of the easy dyeable polyester (EDP) and the polytrimethylene terephthalate (PTT) were investigated in terms of their thermodynamic and kinetic factors, such as standard affinity (−Δμ0), enthalpy change (ΔH0), entropy change (ΔS0), diffusion coefficient (DT) and activation energy of the diffusion (ED). The results were compared with corresponding properties of the PET (polyethylene terephthalate). The −Δμ0 of the EDP and the PTT showed a little higher value than that of the PET. PET displayed the highest negative values of the ΔH0 and the ΔS0, while PTT showed the lowest negative values of them. For all three polyester types, as the temperature increased, the DT increased. PTT had the highest DT at every temperature and PET showed the lowest values of the DT. The ED of the EDP and the PTT was lower than that of the PET.

In order to examine the color change of the disazo acid dyeings on wool fibers, C.I. Acid Blue 113 having disazo groups within the molecular structure was used and its characteristics of the color change were studied. The dye degradation was attributed to the reducing effect of the sulfur-containing amino acids within the wool fibers. The degraded moiety of the disazo dye was analyzed using an LC/MS. The mass spectrum showed that the mass of 326.1 corresponded to the dye moiety having monoazo group, which was formed by a reductive degradation of the disazo dye. From the model studies using cystine and cysteine, it was also found that the formation of the monoazo moiety was attributable to the reducing effect of the cystine and the cysteine.

Heterobifunctional reactive dyes provide great opportunity for efficient dye–fiber reaction due to the mixed double-anchors such as sulphatoethylsulphone and monochlorotriazinyl reactive groups, which may cover a wide range of application temperatures. Four heterobifunctional reactive dyes were applied to nylon fibers using various pH and temperature conditions. The optimized exhaustion (%E) and fixation (%F) were determined. Analysis of dye solutions being adjusted to different pH conditions was carried out to verify the structure of dye moieties. In addition, the acid dyeings having the similar color strength with reactive dyeings were prepared using color matching system to compare wash fastness properties of both the dyed samples. In the case of reactive dyeings, when compared to acid dyeings, the extent of reduction in color strength that occurred during repeated washings was very low and the shade of the dyeings was little changed.

Adsorption properties of the 10 kinds of disperse dyes having different substituents were examined using several representative non-aqueous media on to poly(ethylene terephthalate) substrates. The dye adsorption amounts in pentane medium representing alkanes were much higher than those in the other non-aqueous media. In pentane medium, as the hydrophobicity of the dyes resulting from the substituents of dye molecules increased, the solubility of the dyes increased and the corresponding dye adsorption greatly decreased. This finding was coincident with the results from the previous study that the adsorption amount of disperse dyes on to substrates was inversely proportional to the solubility of the dyes. Furthermore, the hydrophobicity and the hydrophilicity of the dyes were discussed in terms of the electric dipole moments which are obtained by a semiempirical method using molecular modeling software.

A novel hetero-bi-functional reactive compound was synthesized. It was designed to provide different reaction behaviors resulting from α,β-dibromopropionylamido and dichloro-s-triazinyl reactive group. To determine whether the reactive compound (DBDCBS) as a bridging part could combine disperse dyes and cellulosic fibers, three different disperse dyes were used to dye the cotton fibers pretreated with the novel reactive agent. The disperse dyes used were 1,4-dihydroxyanthraquinone (DHAQ), 1-amino-4-hydroxyanthraquinone (AHAQ) and 1,4-diaminoanthraquinone (DAAQ). These dyes contain none-, mono- and di-amino groups in their structures, respectively. Especially, the satisfactory dyeing results were achieved by the disperse dyeings of 1,4-diaminoanthraquinone (DAAQ) due to having two amino groups within the structure. The fastness properties of DAAQ dyeings showed very higher grades in terms of grey scale assessments due to their covalent bonding characteristics.

A novel bridge compound having hetero-bi-functional reactive groups was synthesized. It was designed to contain two different reactive groups such as α,β-dibromopropionylamido and dichloro-s-triazinyl group within the molecular structure. The α,β-dibromopropionylamido group shows considerable reactivity towards amines or amino groups at acidic condition and high temperature. In contrast, the dichloro-s-triazinyl group has reactivity towards hydroxyl groups at alkaline condition and room temperature. In order to examine whether as a bridge the compound could combine dyes containing amino groups with cellulosic substrates, a disperse dye containing amino group was tried to dye the cotton fibers pretreated with the reactive compound. In this context, it was investigated that the synthesized compound was treated by using several experimental conditions such as temperature, pH, neutral salt, treatment time and concentration of the compound. It was also found that the compound of hetero-bi-functional reactive groups showed the feasibility as a bridge agent to combine the cellulosic fibers and the disperse dyes having amino groups.

The dyeing behaviors using indigo vat dye on conventional and microfiber polyester and its fastness properties to washing were examined. Acid leuco dyeing technique with acetic, formic and citric acids was considered. The effect of urea addition to improve the dye build-up was also investigated. In addition, repeated multiple washings of indigo dyeings, which were compared to the results of disperse dyeings, were carried out to determine the fastness properties. From the obtained results, it is found that acid leuco form provided a satisfactory dye uptake at different pH ranges and that the improved dye build-up characteristic was achieved by urea addition due to increasing dye solubility and dye penetration within the substrates. The fastness to washing of indigo dyeings was more effective than that of comparable depth of disperse dyeings.

A reactive anionic agent containing dichloro-s-triazinyl reactive group was synthesized and applied to the cotton fabric. Berberine as a natural cationic colorant showed considerable substantivity towards anionic agent modified fabric. This Berberine can be also employed in antimicrobial finishes as a natural agent due to its characteristic of cationic quaternary ammonium salt. It was found that the adsorption of Berberine onto cotton fabric pretreated with the anionic agent was greatly increased when compared to that of untreated counterpart. The addition of neutral salts was greatly effective to increase the exhaustion–fixation efficiencies (%EF) of the anionic agent onto the cotton fabric. In terms of antimicrobial activity of Berberine dyeing, the dyed sample with Berberine showed very effective antimicrobial functions showing about 99.5% of bacterial reduction against Staphylococcus aureus.

Various non-aqueous media were employed to examine the adsorption and solubility properties of disperse dyes on poly(ethylene terephthalate). The dye adsorptions in alkane media were much higher than those in other non-aqueous systems. The adsorption of disperse dyes on poly(ethylene terephthalate) increased with decreasing number of carbon atoms of alkane groups. In the case of relationships between dye adsorption and dye solubility in various non-aqueous media, the adsorption of the dye is linearly and inversely proportional to the dye solubility in the logarithmic plot. The adsorption dependency on the solubility of dyes was shown to have a similar pattern for different disperse dyes.

Polyester fiber was dyed with indigo vat dye to examine the practical dyeing feasibilities and behaviors. Vat dyes, which commonly applied to the cellulosic fibers, could be considerable colorants to dye polyester substrate, especially focusing on fastness aspect in terms of washing test. In this work, the optimized dyeing conditions and behaviors were investigated. In addition, extended multiple washings of indigo dyeing, which were compared with the results of disperse dyeing, were carried out to determine the fastness properties. HPLC analysis showed that when dyeing time increased, structural changes of indigo components were attributed to the decreasing color strength of dyeings. From the comparison of indigo disperse system and leuco system, it was found that disperse system of indigo had little effect to achieve dye uptakes.

Berberine, a natural cationic colorant, is the major component of Amur Cork tree extract. Due to ionic interactions, while it shows high exhaustion towards protein fibers such as wool and silk, it exhibits little substantivity onto cellulosic fibers. In this context, in order to apply the colorant to cellulosic fibers, the new approach of employing the anionic agent containing a dichloro-s-triazinyl reactive group was conducted. Berberine could display considerable substantivity towards anionic agent finished fibers. It was found that the anionic agent was covalently bonded to the cellulosic substrates by virtue of the covalent nature of its attachment to the fibers and also gave anionic sites to the substrate for electrostatic interaction with cationic Berberine. The effectiveness of the anionic agent in improving the exhaustion of Berberine on the cellulosic fibers was achieved.