Ozonation of aqueous azo dye in a semi-batch reactor

The ozonation of wastewater containing azo dye in a semi-batch reactor has been studied. Results revealed that the rate of ozone transfer increased with increases in the initial dye concentration, the applied ozone dose and temperature. A model was developed to predict the enhancement factor of ozone mass transfer. This model enables the ..

True colors

The article is intended to raise awareness of the potential of color management and give pointers to its successful implementation. Rainier Industries of Seattle has been in the forefront of color management for their fabric advertising business; Event Promotion Supply of Denver prefer to use a mix of CM devices and the human eye. More in..

Continuous colour measurement

Mahlo GmbH & Co Kg have developed the Color Inspection System COLORSCAN, type CIS-10A, to monitor colour continuously and consistently at high line-speeds. The article describes the features of the COLORSCAN, the stages in the processing chain where it is mainly used, now to get the most consistent results, and the benefits associated wit..

Expert system for colour matching

Ciba specialty Chemicals has extended its COLPOCA software (Color Position Calculation) to include exhaust and pad dyeing. As well as providing the recipe for the desired shade, COLPOCA is claimed to facilitate cost-effective reconditioning and re-use of residual past. The new version is designed for recipe formulation with previously def..

Improved determination of indigo on fibers or fabrics

A rapid, accurate spectrophotometric method of determining concentrations of indigo on dyed yarns and fabrics was developed. Indigo dyed yarns were extracted at 45C with an aqueous solution containing triethanolamine, ferrous sulfate, and sodium hydroxide. The resulting leuco indigo solution was analyzed spectrophotometrically and found t..

Controlling dye migration in a fabric capillary network

The objective of this study was to investigate whether a combination of borax and PVA could be used as an antimigrant for soluble dyes, an alternative to using xanthan gum. This cost-effective method also has potential to provide good dye fixation properties. Two sets of pad baths were used, each consisting of varying concentrations of bo..

Synthesis and evaluation of organic pigments. 2. Studies of bisazomethine pigments based on planar nonmutagenic benzidine analogs

The synthesis, characterization, genotoxicity and light fastness of thio-and oxopyrimidine based bisazomethin pigments prepared from a series of nonmutaenic benzidine congeners is reported. Whereas bisazomethine pigments based on benzidine and 3,3'-dimethylbenzidine were mutagenic in both the Ames assay and the prival modification of the ..

Supercritical fluid technology in textile processing: An overview

In light of environmental concerns, the textile industry has accelerated efforts to reduce or eliminate water consumption in all areas of yarn preparation, dyeing, and finishing. Supercritical fluid dyeing technology has the potential to accomplish this objective in many commercial textile applications around the world, both at present an..

Effects of additives on the dyeing of nylon-6 with dyes containing hydrophobic and hydrophilic moieties

A series of azo disperse dyes with variable hydrophobic chain length and hydrophilic (hydroxy or glucosyl group) head were synthesised. 1H and13 CNMR spectra indicated that the glucosyl moiety was linked to the azo structure with a β anomeric bond. The dyeing properties on polyamide fibres were assessed with dyeing isotherms and Linitest ..

Theoretical and practical aspects of the Tactel Coloursafe reactive dyeing system for modified nylon 6,6

Three, commercial Stanalan reactive dyes were applied to Tactel Coloursafe knitted fabric at different pH values and the extents of dye exhaustion and fixation were determined. The three dyes displayed similar characteristics in terms of dye exhaustion and dye fixation. High exhaustion was achieved and his reached a maximum in the region ..