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A series of compounds that have potential as environmentally-friendly inorganic pigments have been prepared using solid-state methods. The materials have been characterised using a variety of techniques including powder X-ray diffraction, colour measurements, EDX, Mössbauer spectroscopy and solid state NMR. Materials based on the industrial pigment, ultramarine blue, have been investigated using a variety of methods to determine the source of the favoured red-hue. Industrial materials of different shades as well as laboratory synthesised and ion-exchanged ultramarine materials have been analysed for colour, impurities using bromine insoluble method and structure by Rietveld analysis. ICP analysis has been shown to have limited success in determining the AI:Si ratio for ultramarine materials. The role of small levels of potassium in the formation of red-shade blue and the introduction of impurities by the use of feldspar in the industrial formulation has been confirmed. The investigation of a green pigment based on CuO-B203 mixtures has been investigated by varying the ratios of the two components. In the copper-rich region, the materials produced have similar colour properties to the industrial green standard, chrome oxide. The blue boron-rich materials have relatively poor pigment properties and the colour weakens dramatically on grinding and mixing with diluents such as titanium oxide. The poor acid and water stability of the products suggest that the use of these materials as pigments would be limited. A solid solution in the CoO-A1203-GeO2 spinel system has been investigated. As the germanium level increases, the firing temperature required to produce a pure phase decreases. The samples range in colour from blue at the aluminium-rich end through purple to pink at the germanium-rich end. The use of mineralisers appears to have a favourable effect on the colour of the materials. Rietveld refinement of the materials suggests that the series shows disordering of the cations over both tetrahedral and octahedral sites and that the materials become cobalt deficient as the aluminium level increases. Doping, annealing and mineralisation of the SnO-Nb2O5 series using cation (V, Ca, Ta) and anion (Cl, S) doping has produced two different phases with very different properties. The foordite structure, SnNb2O6 is a very stable stoichiometric yellow phase that shows good temperature and gaseous environment resistance. The pyrochlore phase, SnII2x_N, b2y.S n7yO7_7h, owever is very susceptible to changes in atmosphere and readily undergoes substitution at both anion and cation sites to produce phases that vary in colour from yellow through to red. The product phases have mixed divalent and tetravalent tin across two different sites. Substitution of some of the oxygen with sulfur (to a limit of 0.3 per unit cell) leads to a reddening of the sample and stabilisation of the divalent tin within the structure. Mössbauer analysis indicates the presence of both divalent and tetravalent tin in the compound where the level of tin (IV) decreases on substitution of sulfur. Thermal treatment of both tin samples facilitates a reversible temperature dependent change in the colour of the samples from yellow/orange through to bright red. Temperature dependent XRD analysis has shown that the colour change does not result from a change in the structure.

The continuous coating of steel and galvanised steel coils is referred to as coil coating. Coil coating is considered the most efficient coating method with regard to the amount of coated area per unit of time. Coil coatings include primer coating, top coating and backside coating. In general, the primer coating and top coating need to balance effectively among flexibility, adhesion, and film hardness. As such, saturated polyester resins with the capability of being molecularly engineered have found applications in coil coatings as the key binder. Nowadays, a combination of up to five polyester resins with different molecular structures are employed in coil primer coatings and coil top coat coatings to derive hard yet flexible coatings. The aim of this study was to synthesise and characterise a novel and standalone polyester resin system that would provide multiple properties simultaneously, thus, eliminating the need to use mixtures of polyesters in coil coatings. The multiple properties concerned included high flexibility, excellent adhesion and sufficient chemical resistance. For development of the polyester resin system concerned, a variety of polyols and dicarboxylic acids were polymerised to form polymeric polyester binders. Direct esterification polymerisation technique was employed for synthesis of the polyesters. The results obtained at an early stage indicated that in order to develop such a single resin system, achievement of an optimum balance among flexibility, adhesion and glass transition temperature was essential. Differential scanning calorimetry (DSC) showed that the augmentation or reduction of the glass transition temperature of the saturated polyester led to the augmentation or reduction of the film hardness of the resulting coil coating. Thus, a unique blend of neopentyl glycol, 1,4 cyclohexanedimethanol,1,6 hexanediol, adipic acid, isophthalic acid, and terephthalic acid was polymerised. The resulting product performed efficiently as a standalone binder system in a coil primer coating and a coil top coating, providing all of the required properties. Mglecular structures of the saturated polyesters synthesised were confirmed by carbon-13 and proton CH) nuclear magnetic resonance (NMR) and Fourier transformed infrared (FTIR). Alterations made to molecular structure of the polyesters through partial replacement of their diots with new ones were visible in expected frequency ranges of the resulting 13CNMR and 1HNMR spectra. According to size exclusion chromatography (SEC), molecular weight characteristics of the pilot scale and the industrial scale reproductions of the novel, single component coil coating polyester resin system developed were comparable with the initial product synthesised at the lab scale.

In the current work novel navy and black fibre-reactive dye molecules were designed, synthesised and evaluated technically against the market leading dye, C.1. Reactive Black 5. Novel intermediates were synthesised using a Michael-type addition of 4aminophenyl- p-vinylsulphone onto various primary and secondary amines. The resulting novel bis(aminoaryl) intermediates were isolated and characterised, before being tetrazotised and utilised as linker molecules in the synthesis of four novel reactive dyes, each possessing two 'twice coupled H-acid' units. These reactive dyes were then applied to cotton in an exhaust dyeing process, at different concentrations, and their dyeing performance was compared to that of the market leading dye. The novel dyes were up to 20% stronger on the cloth than the reference dye. This first series of dyes derived from novel linker intermediates had molar extinction coefficients of around 90,000 L mor1 cm-1 . The second series of dyes was derived from commercially available linker intermediates, which allowed a different degree of electron transfer from one chromophoric part of the molecule to the other. As a result of electron transfer, the molar extinction coefficients increased up to 144,000 L mor1 cm-1 . It was found that the structure of the linking molecule has a significant influence on the 3-dimensional structure of the overall dye molecule and thus on its dyeing performance, for example the dye derived from 3,3'-diaminodiphenyl sulphone performed much better, than its para-isomer. Arising from the unexpectedly large difference in technical properties of isomeric dyes, a series of eight isomeric dyes was synthesised and evaluated. The differences in dyeing performance were clearly related to their 3dimensional structures. It was found that dyes possessing a meta-sulphone linker were technically superior to the para-isomers. The isomers with meta structures appeared more hypsochromic with a wider half band width, while the para linker had a bathochromic influence and having a shorter half band width. All dyes performed better, at high concentrations, when applied at higher temperature, i.e. 80°C compared to 60 °C, possibly attributable to their size. A fourth series of four novel bis(monochlorotriazinyl) dyes was prepared from an identical dyebase, but with varying degree of sulphonation. This resulted in different levels of anionic charge, which influenced the dyes' solubility and dyeing performance. A number of eight sulphonate groups was found to be the optimum in terms of solubility and dyeing performance, but that the optimum number of sulphonate groups is strongly dependent on the type of chromophore.

Over the last 20 years, selected disperse dyes and bis-3-carboxypyridinium-striazine reactive dyes have been widely promoted for the exhaust dyeing of polyester/cotton blends in a one-bath-one-stage ('All-in') process under neutral conditions. However, despite the time and energy savings afforded by this elegant dyeing process, there is a belief in the dyeing industry that economical production is limited to pale and medium depths of shade. The two dye classes (disperse dyes on polyester and bis-3-carboxypyridinium-striazine reactive dyes on cotton) were investigated to understand why heavy depths of shade could not readily be obtained, economically, using this process. The bis-3carboxypyridinium- s-triazine reactive dyes were responsible for the inability to achieve heavy depths of shade, economically, when dyeing at 130°C and neutral pH. The poor colour yield of the dyes was due to their low exhaustion level and low fixation efficiency at 130°C and pH 7.0-7.5, particularly when compared with the parent bis-monochlorotriazine dyes, fixed under alkaline conditions at 80°C. The synthesis and evaluation of some bis-3-carboxypyridinium-s-triazine reactive dye structures, possessing highly substantive chromophores, were investigated as a mecm of obtaining high colour yield, on 100% unmercersised cotton, at 130°C and pH 7.0-7.5. When a highly substantive bis-3-carboxypyridinium-s-triazine dye chromophore was incorporated into the reactive dye structures, heavy depths of shade could be readiiy obtained when dyeing at 130°C and neutral pH, using conventional salt concentrations. However, the wet fastness properties of the dye were poor, due to the slow removal of the hydrolysed dye and its propensity for back-staining adjacent white areas. If the high substantivity of a dye could be assigned to the reactive group, which is removed during the fixation of the dye, it may be possible to offer both acceptably high levels of build-up (and costeffectiveness) and wet fastness. The synthesis and evaluation of novel reactive dye structures, possessing substantivity-conveying reactive groups, when applied to cotton at 130°C and pH 7.0 - 7.5, were investigated. When a substantivity-conveying reactive group was incorporated into a reactive dye structure, as a replacement for a chlorine atom, the dye exhibited a higher substantivity than the parent monochlorotriazine dye. The use of amide derivatives of nicotinic acid as the reactive group in a s-triazinyl reactive dye resulted in an increase in the substantivity, compared with the parent 3carboxypyridinium- s-triazinyl dye. When two substantivity-conveying reactive groups were incorporated into a dye molecule, without changing the reactivity of the dye, the above effect is enhanced, resulting in higher colour yield than from the corresponding Kayacelon React dye. Since the substantivity-conveying reactive group is removed during the fixation of the dye, the high substantivity of the parent dye should not be an impediment to achieving good wet-fastness properties, without the need to use excessively long wash-off sequences.

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Colour difference evaluation is an important quality control task for the surface colour industries. It has been carried out by visual assessments of surfac7samples by the experienced colourists. However, many viewing parameters such as sample' size, sample separation, textures could have an impact on the perceived colour differences. Recently, evaluations have also been' performed using self-luminous colours to achieve quick response for modem business. Large difference in the viewing conditions between the surface and self-luminous media could also affect the final decision for judging colour difference. This study was divided into two parts according to the different media used, surface and self-luminous (CRT) colours. The goal was to investigate various parametric effects for assessing colou,r differences including medium, texture, sample separation, sample size, and background colour. Experiment 1 included 107 cotton pairs corresponding to five colour centres. The average colour difference of the sample pairs was about 5 CIELAB units. The grey scale method was used for scaling colour differences \vith a panel of 10 observers (two assessments for each observer). In general, the parametric effects found were small varying from 8 to 15% except for the background ~ffect, i.e. 42% and 26% for green sample pairs assessed against a green background and the blue samples pairs against ..' a blue background respectively. The r~ults clearly indicate a chromatic crispening effect. Experiment 2 included six phases which reproduced the colours in Experiment 1 onto a CRT. The results confirmed that all the parametric effects found in Experiment 1 and the most obvious effect was the chromatic crispening effect. It was intended to compare results between Experiments 1 and 2 to reveal the difference between surface colour and self-luminous colour under various parametric conditions. The results showed that all CRT colour pairs appear about 20% smaller colour difference than surface c'olour pairs.

Six commercial photochromic dyes were applied to polyester and, to a lesser extent, cotton fabrics by different dyeing and printing methods. The photochromic performance of the dyed and printed fabrics was investigated in terms of the degree of photocoloration, background colour, fading characteristics, fatigue resistance and storage stability. A traditional aqueous-based disperse dyeing method was used to apply the photochromic dyes to polyester fabric. Solvent-based dyeing methods also were investigated for application of the photochromic dyes to polyester fabric. Solvent-based inks were formulated and applied to polyester and cotton fabrics by digital inkjet printing. The photochromic performance and colour fastness to light and washing of the photochromic fabrics were evaluated and comparison made. UV/visible spectra of the commercial photochromic dyes in a range of solvents were obtained and interpreted in terms of solvent polarity. On the basis of this study, the photochromic performance of the fabrics was improved by selecting the appropriate application solvents which transferred minimum background colours onto the fabrics. A new method of evaluating lightfastness of photochromic fabrics was established, aimed at replacing the conventional method by an instrumental method. This method was based on comparing the decrease in the degree of photocoloration of photochromic fabrics after light exposure with measured values of the colour differences of the blue wool references after fixed periods of light exposure. Two photochromic dyes were synthesized by azo coupling of a spironaphtho[2,1-b]oxazine with diazonium salts obtained from p-nitroaniline, and m-nitroaniline. Molecular modeling of the new photochromic systems, which are referred to as azospirooxazine dyes, showed that the dyes were predicted to have the potential to show photochromism. Thus, the photochromism of the azospirooxazine dyes in a range of solvents was investigated. The investigations showed that the dyes performed differently in different solvents in terms of the hue, the rate of the photochromic colour change and the colour reversibility.