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An alkaline dyeing of polyester with an alkali-stable disperse dye, Dianix 1 Scarlet AD-RG, was developed using sodium edetate as an alkaline buffering agent. The results obtained indicate the suitability of using sodium edetate for alkaline dyeing of polyester when compared with the control alkaline dyeing using Dianix AD system. Selected mono and bifunctional reactive dyes were used in combination with the alkali-stable disperse dye for dyeing of polyester/cotton blend. Different dyeing methods for cotton and polyester/cotton blend fabrics using sodium edetate were evaluated in comparison with their respective control alkaline dyeing methods. The results of using sodium edetate in one-bath two-stage and two-bath dyeing of polyester/cotton blend were comparable with that of the control dyeing method. Particularly, no change in the leveling and fastness properties was evaluated for all samples irrespective of the dyeing method.

Urea reduction or elimination in reactive dye print pastes is of ecological interest. Sodium edetate is presented as a complete substitution of urea in the conventional print paste of reactive dyes, namely CI Remazol Black B and Remazol Brilliant Orange 3R using a constant amount of sodium alginate as the thickening agent. Three different print pastes containing urea/NaHCO 3 , sodium edetate/NaHCO 3 and sodium edetate were thoroughly investigated. Different factors that may affect the printability of cotton, such as the concentrations of sodium edetate, urea, dye, absence or presence of alkali and steaming time in the prints obtained were evaluated with respect to the dye fixation, colour strength, dye penetration, levelling and the fastness properties. Excellent to good fastness was obtained for all samples irrespective of the print paste used.

A new Chromone, 7,8-dimethoxy-2-[2-(3'-acetoxyphenyl)ethyl]chromone (1) was isolated from an acetone extract of the Cambodian agarwood along with two known chromones, 6-methoxy-2-(2-phenylethyl)chromone (2) and 6,7-dimethoxy-2-(2-phenylethyl)chromone (3). In addition, an abietane ester (4) and the sesquiterpene dehydrofukinone (5) were isolated from the agarwood oil of the same origin. Structural elucidation of all isolated compounds was made based on IR, 1H and 13C NMR spectroscopic data.

Reactive cationic agents, phenylmonochlorotriazinyl and epoxypropyl, are used for cotton pretreatment using a pad–dry–curing technique. The dyeability of cationised cotton fabrics using CI Acid Red 1, determined spectrophotometrically for the residual dyebath, has been dependent on the cationic agent concentration and the appropriate mixture used. Comparative sorption isotherms, rate of dyeing at different temperatures, standard affinity, entropy and heat of dyeing for three different pretreated fabrics have been calculated and discussed. The equilibrium data obtained were fitted by the Langmuir isotherm model, allowing the corresponding sorption parameters to be determined.

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The synthesis of a new reactive disperse dye containing the disulphide bis(ethylsulphone) group is described. The dye has been applied to nylon 6 and silk fabrics at a variety of pH and temperature conditions. Optimum dye exhaustion and fixation were achieved at pH 8 and 130 °C. The results of dyeings on both substrates indicate that the model disulphide bis(ethylsulphone) reactive disperse dye shows a higher degree of exhaustion and fixation on silk than on nylon 6. The fastness and levelling properties on both fabrics were good.

A new bifunctional reactive disperse dye containing a temporarily anionic sulphatoethylsulphone and a nonionic disulphide bis(ethylsulphone) groups was synthesised and applied to nylon 6 fabric by the exhaust dyeing at a variety of pH and temperature conditions. A monofunctional reactive disperse dye containing only nonionic disulphide bis(ethylsulphone) group was also synthesised and its dyeing behaviour was compared with the bifunctional dye. The bifunctional reactive disperse dye exhibited high exhaustion and fixation values at pH 6 and 120°C. The results also indicate that the combination of temporarily anionic and nonionic reactive groups of the bifunctional dye provided great enhancement in dyeing performance compared to that of the monofunctional dye. The dyes also showed very good levelling and fastness properties on nylon 6 fabric.