An algorithm, called the WSF algorithm, was developed which could predict the dyers‟ attributes of colour difference (depth, ΔD, brightness, ΔB, and hue, ΔH*) from the reflectance values of a pair of dyeings, enabling the dyer to take full advantage of colorimetric analysis. The algorithm was based on extensive experimental work to map surfaces of constant visual depth throughout the colour space and the thesis describes the methodology and the necessary calculations to determine the ΔD, ΔB and ΔH values of a pair of dyed samples. This algorithm was compared to other existing algorithms (the DBH and the Sato models) using two data sets with 49 dyed pairs for data set 1 and 117 dyed pairs for data set 2 respectively. The correlation of the values of ΔD, ΔB and ΔH determined using the WSF algorithm with the DBH and the Sato models showed an excellent relationship between these three algorithms for both the data sets. Qualitative comparison of the visual assessments of data set 2 with the WSF algorithm was encouraging but the quantitative comparison of the visual assessment for data set 1 was disappointing. The pre-requisite of the WSF algorithm is the six equi-depth surfaces which have been defined numerically in the CIELAB colour space and previously reported as WSI depth surfaces. The first stage of this algorithm was to generate, using the WSI algorithm, the equi-depth line in the L* C* plane that passes through the L* C* coordinates of the standard. The K/S values of the batch were then iterated, until its depth became equal to that of the standard. At this point, the precise location of the batch on the equi-depth surface might be different from that of the standard. The linear distances between the batch and the standard, gave the differences in depth and brightness between the standard and the batch. A new approach was investigated for the hue correction of dyed pairs, where the hue of the batch was different from that of the standard. Real data of highest possible chroma values from Munsell colour atlas were used to create maximum chroma boundaries which were found necessary for the hue correction of the batch. It was noted that the DBH and the Sato models also incorporated hue correction of the batch. The WSF algorithm described in Chapter 4 contained an iterative stage which created an additional complexity in programming. Therefore an alternative version of the WSF algorithm was developed, called the linear WSF model, which avoided the need for iteration and yielded the same results. This linear WSF algorithm strongly correlated with the WSF (iterative) model and also to other empirical models as well.

This thesis describes a new investigation into the relationship between the developed colour intensity of photochromic textiles and the time of UV exposure and also the time of relaxation. As a result of this relationship the potential of flexible textilebased sensor constructions which might be used for the identification of radiation intensity is demonstrated. In addition the differences between photochromic pigment behaviour in solution and incorporated into prints on textiles are demonstrated. Differences in the effect of the spectral power distributions of light sources on the photochromic response are also examined. Bi-exponential functions, which are used in optical yield (Oy) calculations, have been described to provide a good description of the kinetics of colour change intensity of photochromic pigments, giving a good fit. The optical yield of the photochromic reaction Oy is linearly related to the intensity of illumination E. The optical yield obtained from the photochromic reaction curves are described by a kinetic model, which defines the rate of colour change initiated by external stimulus of UV light. Verification of the kinetic model is demonstrated for textile sensors with photochromic pigments applied by textile printing and by fibre mass dyeing. The thesis also describes a unique instrument developed by author, which measures colour differences ΔE* and spectral remission curves derived from photochromic colour change simultaneously with UV irradiation. In this thesis the photochromic behaviour of selected pigments in three different applications (type of media – textile prints, non-woven textiles and solution) is investigated.

The property of flow and the transfer of dye through the yarn assembly in a package dyeing process is modelled and simulated to provide a kinetic understanding of the package dyeing process. A novel approach to the modelling of flow in porous media and dye transfer through the package has been presented. The flow properties in package dyeing process have been described by coupling the Navier-Stokes equations with Brinkman equations. The Navier-Stokes equations were also combined with Darcy's law for comparison. The dye concentration in dyebath and on fibres throughout the package has been defined by the mass transfer model, which involved the factors of dispersion, convection, and various adsorption isotherms. The simulation results of the flow model present the velocity and pressure distribution of the flow in the tube and yam assembly. The influence of package factors, such as package size, shape, density, and process parameters, such as flow rate, flow direction, dye/fibre type, and dye concentration in the mixing tank on the outcome of the dyeing process have been examined based on the mass transfer model. The relevant adsorption isotherms can be selected for different dye/fibre combinations, to simulate the dye dispersion process through the package. The relationship between various dye dosing profiles and the degree of levelness achieved is also demonstrated. The use of computational methods to simulate the dyeing process is proved to be a powerful tool providing a kinetic understanding of the flow phenomena and dye transfer in package dyeing process. The predicted behaviour of the liquor flow in both tube and porous package, as well as the dye concentration distributions across the package under different conditions, appear to be in qualitatively good agreement with available experimental data. These models can also be used to design package dyeing apparatus, and select suitable material for the construction of tubes taking into account the static pressure predictions under different flow rates. The selection of correct type of flow meter, and pressure sensors based on their simulated range can also be carried out.

This thesis examines the process and structures of the formation of taste and activation of fashion change within the British printed calico industry, from 1919- 1940. The approach taken was to analyse the style trends, economic conditions and strategic policy of a number of case study companies. These case studies are contextualised by analysis of the broad structural and economic conditions in the industry, the interventions of Government and the contemporary ideological construction of pattern design. The thesis tests several historiographic views relevant to the structural analysis of taste formation. The assertion by the Balfour Committee in 1928 that the industry was divided into separate market and design style sections is investigated. A commonly held view that British interwar design was reactionary and regressive, and the general assumption that Modernism came to Britain in the 1930s as a Continental influence, is challenged. Definitions and perceptions of Modernism are closely examined. A range of contradictory claims regarding the sources of design innovation and fashion leadership in the industry are assessed. In addition, claims that the British interwar cotton industry was not innovative in its response to economic conditions and theories of a link between macroeconomic conditions and innovation are considered. In relation to the formation of taste, the thesis concludes that there was a separation in the fields of taste construction for furnishing and dress fabric, with different sources of design production, markets and design styles, although textile production for both sections could occur within the same company. In the case studies analysed, the main source of innovation and taste construction in printed textile design appears to have been company design studios, rather than freelance artists, architects, designers or Parisian design studios. The influence of the economic context was evident in the impact of specific cost rises, alteration of print processes used and changing market demand due to macroeconomic conditions and international competition. A switch in the basis of mass market demand from durability to fashion in textiles and clothing during the interwar period promoted a production structure of short production runs, small orders and a wide design range. A relevant factor in the construction of taste Was the Modernist educational aims of the British Government during the interwar period, particularly in the impact on general and designer education. It switched to a policy of promoting exhibitions of innovative Modernist design as a basis for creating demand in the 1930s, from a strategy that emphasised vertical integration of the textile industry to increase efficiency. The British printed textiles industry was innovative in its response to severe economic conditions, in terms of design, product development and the strategies of national printed textile industry organisations. A significant finding is the active role of the British printed textiles industry in initiating debate, producing exhibitions and developing designs that by 1919 had established a Modernist approach and visual language of decorative design. This version of Modernism was related to art-based concepts of form and expression, while also considering the design criteria of fitness to function. Dress fabric design - not hitherto seen as significant in the historiography of Modernism - was shown to have been strongly Modernist in emphasis in the case study companies examined. Modernism in pattern design appears to have been popular during the interwar period, rather than - as generally assumed - restricted to a small group of consumers with highly educated aesthetic tastes. These conclusions arise from and are substantiated by extensive empirical investigation of the design style and business history of case-study companies, supported by structural analysis of the industry.

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No description available.

No description available.

The main aim of this research was to develop novel nanocomposite PVD coatings for magnesium alloys, to improve their wear and corrosion resistance – and thereby explore the potential to extend the use of such alloys to moving parts for light-weighting of tribological components, where the potential for cumulative weight savings is immense if key parts can be made from magnesium, but the alloys cannot currently be used successfully due to their poor wear and corrosion behaviour under dynamic loading. The work comprises two main stages. The first stage was to produce a base layer for subsequent PVD ceramic nitride (or nitrogen-doped hard metallic) coating deposition. The second stage was to deposit a nanocomposite coating with improved tribological performance, by introducing sequentially nitrogen reactive gas, subsequent to the base layer preparation step. In the first stage, sixteen AlCuMoMgZrB PVD coating layers were prepared by pulsed direct current closed-field unbalanced magnetron sputtering. Four deposition runs were carried out, with substrate negative bias voltages of 50 V, 60 V, 75 V and 100 V being applied. For each deposition run, four proprietary WE43 magnesium alloy substrates were placed at different positions (P1-P4) on the substrate holder, between AlMgB and ZrMoCu composite sputter targets mounted at 90° to each other. Investigations into composition, microstructure, mechanical and electrochemical properties were then carried out, to select the most suitable base layer. The P1-60 layer (i.e. deposited at P1 position, closest to the AlMgB composite target, with substrate negative bias of 60 V) was chosen as the most suitable candidate amongst the sixteen AlCuMoMgZrB coating layers due to its superior mechanical properties, electrochemical properties, and amorphous microstructure. In the second stage, four novel AlCuMoMgZrB(N) nanocomposite PVD coatings with different nitrogen reactive gas flow rates (i.e. 5 sccm, 10 sccm, 15 sccm and 20 sccm), introduced partway through the sputter deposition process, were produced sequentially, on top of the selected P1-60 base layer. Further detailed investigations into composition, microstructure, mechanical, tribological and electrochemical properties were performed to evaluate the improved wear and corrosion resistance. For practical applications, P1-60-15sccm (46.27 at.% Al, 8.71. at.% Mg, 5.35 at.% Cu, 3.63 at.% Mo, 1.30 at.% Zr, 2.65 at.% B and 32.08 at.% N) seems a likely candidate to provide an optimal combination of wear and corrosion resistance – in terms of the best and the second-best performance in micro-abrasion and in corrosion tests, respectively.

In this work, an advanced (AC)DC/OCP/AC cyclic test regime has been developed (and validated experimentally) as a new tool for the evaluation of the corrosion behaviour of metallic substrates and/or electrically-conductive coatings. Incorporation of concurrent solution pH measurement with the advanced (AC)DC/OCP/AC technique developed in this work, qualifies this approach to be applied in different industrial applications, such as in aircraft, nuclear and biomedical sectors. It provides opportunities to evaluate objectively the detailed corrosion behaviour in shorter exposure times (as little as 1 day) compared to the widely-used and accepted (but highly subjective) salt spray test (SST) and to conventional (periodically repeated but laborious) electrochemical impedance spectroscopy (EIS) evaluation at open circuit potential (EOCP). The (AC)DC/OCP/AC cyclic test provides valuable information concerning the corrosion behaviour of uncoated Al 6082 alloy (repeat tests are performed, to eliminate test protocol variables and improve the robustness of the test). The three examples of prototype PVD Al-based nanostructured coatings (AlCr, AlCr(N) and AlCrTi), deposited on 17/4 PH steel, were then evaluated from a scientific perspective, to acquire a fundamental understanding of their performance and degradation with time. The results are shown in two main sets; i) electrochemical results obtained at EOCP and six repeated cycles of (AC)DC/OCP/AC cyclic testing and ii) solution pH results during continuous monitoring of the cyclic electrochemical test procedure. AlCrTi coating showed the best corrosion resistance after application of six successive DC/OCP cycles as a sacrificial protection for the substrate, followed by the AlCr(N) and AlCr coatings. However, the repassivation behaviour exhibited by the AlCr(N) coating after breakdown during extreme DC polarisation, may suggest an advantage to use this coating preferably in aerospace applications because of its strong ability to self-heal. This might be promising for future coating materials for corrosion protection where cadmium or hard chromium needs to be replaced. In addition, the structural and chemical composition of these samples was characterised using SEM and EDX analysis. Conventional open circuit potential (EOCP) and potentiodynamic polarisation scans were also employed, to determine the ‘as-received’ corrosion behaviour.

This thesis describes the design, synthesis and technical evaluation of a series of novel anionic agents designed to prevent the staining of cotton, by loose dye residues, during laundering. These Resist Agents, which were added to the wash liquor, became bound to the cotton by intermolecular bonding, thus increasing the net negative charge at the surface of the cotton and thereby increasing its resistance to staining by anionic dye residues. Each agent comprised two triazine rings joined by one of three linking groups: 4,4'- diaminostilbene-2,2'-disulphonic acid, p-phenylenediamine or piperazine, and possessed a number of anionic sulphonate residues. 23 of the synthesised agents were tested as wash bath additives. All resulted in a reduction in the level of staining of cotton by a reactive dye; the magnitude of this effect varied greatly but, generally, it was observed that larger agents with a greater level of sulphonation provided the greatest resist effect, though none was as effective as the commercially available dye transfer inhibitor Sokalan HP 56. Surprisingly, one of the stilbene based agents (FB1) was significantly better than Sokalan HP 56 in reducing the staining of nylon fibres by C.1. Acid Blue 113. Further tests showed that all of the stilbene based bis(monochlorotriazinyl) agents with arylamine substituents attached to the triazine rings reduced the staining of nylon fibres by a number of acid dyes, whereas agents with alkylamino groups showed no such effect. In order to gain further insight, the adsorption of some of the agents onto ~ndyed cotton was studied and found to adhere to the Langmuir adsorption Isotherm model, indicating a monomolecular layer at the outer surface of the fibres. This build-up of anionic sulphonate groups at the fibre surface appeared to provide an effective barrier against approaching anionic dye residues and may account for the high levels of stain resist efficacy that were observed. Interestingly, when a similar concentration of sulphonate groups were uniformly distributed within the fibre, a much lower level of resist effect was observed. The percentage exhaustion of the agents onto undyed cotton during a 30 minute wash test was less than 50%, even at low concentrations of agent applied. Additionally, the agents took 24 hours to reach an equilibrium level of uptake onto cotton, much longer than a typical domestic laundering cycle. A Quantitative Structure Activity Relationship Study was conducted to identify the molecular features required for effective dye transfer inhibition on cotton fibres. 13 stilbene based agents were modelled and from these optimised structures, the values for 36 molecular descriptors were obtained. No statistically significant correlations were found between the measured stain resist efficacy and the molecular descriptors, suggesting that the interaction of the resist agents with cellulose is complex. The QSAR study did not yield a reliable predictive model to describe resist agent efficacy, possibly because the number of molecules used in the study was too small and the molecular structures were too closely related, to obtain any meaningful correlations.