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The purpose of this paper is to propose a new method of synthesis of CuO · SiO₂ oxide composite based on the reaction of precipitation from water solutions of sodium silicate and copper nitrate.

Solutions of sodium silicate and copper nitrate were used as substrates. The effects of direction of substrate supply, concentration, excess of reagents and temperature of precipitation on the physicochemical properties of the products were analysed.

A new method of synthesis of CuO · SiO₂ oxide composite based on a precipitation reaction is proposed.

Only sodium silicate and copper nitrate solutions were used.

The CuO · SiO₂ oxide composite obtained can be used as blue pigment or polymer filler.

The paper determines optimum conditions of CuO · SiO₂ oxide composite precipitation to obtain products with desired physicochemical, dispersive and structural properties.

The purpose of this study is to investigate the changes in the performance of ink formulations caused by the addition of compounds that improve the ink’s physical properties to achieve an optimum formulation for inkjet printing, because of the importance and simplicity of this method.

Ink samples were formulated using Acid Red 14 as ink colorant, different percentages of polymeric compounds including polyvinyl alcohol (PVA), polyvinylpyrrolidone and Carboxy methyl cellulose (CMC) as viscosity modifier compounds and surfactant as the surface tension enhancer. Formulated samples were adjusted in terms of fluid physical properties e.g. viscosity, density and surface tension, and the effect of used compounds on the improvement of both physical and colorimetric properties such as viscosity, surface tension, colorimetric coordinates and lightfastness has been evaluated to achieve the optimum printing inks to be printed on three different substrates.

The experimental observations showed that CMC was the most compatible compound as the viscosity modifier as its viscosity value was in the printable range of 2–22 cP. Moreover, a flow-curve test was applied to the ink samples and their Newtonian behavior was approved. Based on the spectrophotometric test results of printed samples, the samples containing PVA provided acceptable lightfastness in comparison to other ink samples on every used substrate.

An optimum relation between colorimetric coordinates of the printed samples and ink formulation could be considered and achieved.

The purpose of this paper is to evaluate and discuss colour properties, stability and lightfastness after accelerated exposure in xenon‐arc light apparatus, of 3D ink jet prints produced by using 3D colour printing process.

3D colour prints were produced using ZCorporation 3D printing method. The samples were divided into groups according to the finishing process applied (untreated, finished with different infiltrants). Colorimetric properties were measured using spectrophotometer. Samples were placed into xenon‐arc based weathering apparatus (Xenotest), using the preset glass filtered sunlight, standard indoor conditions. Colour stability was evaluated as change in colour after repeating the spectrophotometer measurements and comparing spectral and specific colorimetric values of initial and exposed samples.

Based on methodology used, the analysis has shown the changes in colour appearance of differently finished 3D prints, which were mostly attributed to chroma and lightness variations. The colour stability of samples studied noticeably varied and is dependent on colour, percentage of ink coverage and finishing method. Issues of colour and stability of 3D ink jet prints could become important as 3D printing emerges into new application areas, in which the object properties will need to be maintained for a certain amount of time.

The research is comparative and is limited to the specific materials and procedures used.

The paper describes aspects of colour 3D printing for which the published research and literature data are still, for the most part, lacking. Colour measurements methodology and evaluation of stability described could be of value for further research and for users of the technology.

This research deals with a new kind of nanopigment, obtained from the combination of organic dyes and layered nanoclays, that the authors call nanoclay‐colorant pigment (NCP). Whilst they have already been employed in inks and coatings, to date these nanopigments have not been used as pigments for polymers. The existing lack of knowledge surrounding them must be redressed in order to bridge the gap between current academic studies and commercial exploitation. Therefore, the main purpose of this paper is to examine the hitherto unknown aspects of the NCP, which relate specifically to their applicability as a new type of colorant for polymers.

A blue NCP has been prepared at the laboratory according to the patented method of synthesis (patent WO0104216), using methylene blue and montmorillonite nanoclay. It has then been applied to a thermoplastic polymer (linear low‐density polyethylene – LLDPE) to obtain a coloured sample. Furthermore, samples with the same polymer but using conventional blue colorants have been prepared under the same processing conditions. The mechanical, thermal and colorimetric properties of these materials have been compared.

The thermal stability of the sample coloured with NCP is reduced to some extent, while the mechanical strength is slightly increased. Moreover, this sample has better colour performance than the conventionally pigmented samples.

In this paper, a blue NCP has been synthesised and successfully employed with polyethylene and the obtained sample shows better colour performance than polyethylene with conventional pigments.

The aim of the paper was to study the effects of mordanting methods on the absorption behaviour of cochineal natural dye on polyamide fibres.

Iron sulphate and aluminium potassium sulphate salts were used as mordanting agents, and bottom mordanting, meta-mordanting and after mordanting methods were applied in the dyeing of polyamide samples with the cochineal natural dye. Colourimetric evaluations were carried out, and the principal component analysis was used to investigate the spectrophotometric properties of the dyed samples. Fastness properties of the dyed samples were also assessed.

The obtained results indicate that the method of mordanting has a great effect on the obtained shades, absorption behaviour and fastness properties. Based on the results, it was concluded that polyamide fabrics could be successfully dyed with cochineal and combination of dyeing with different mordanting methods, and different mordanting agents would develop the range of obtainable shades.

The textile and apparel industries have been widely criticised for their role in polluting the environment. So, the use of synthetic dyes has been limited and the use of natural dyes has increased. The literature survey indicates that there have been relatively few works investigating the dyeing of polyamide with cochineal natural dye. This research studies the effects of mordanting methods and mordant types on colourimetric and fastness properties of cochineal-dyed polyamide samples.

The health and environmental hazards associated with synthetic dyes have led to a revival of natural dyes that are non-toxic, environmentally benign and coupled with various functions. The study aims to investigate and develop the potentiality of a popular herb called Chromolaena odorata (C. odorata) as a sustainable and stable dyestuff in textiles.

Natural colorant extracted from C. odorata leaves is used to dye the worsted fabric, which is one of the premier end-use of wool in fashion, via the padding method associated with pre-, simultaneous and post-mordanting with chitosan, tannic acid and copper sulfate pentahydrate. The effects of extraction, dyeing and mordanting processes on fabric’s color strength K/S and color difference ΔE_CMC are investigated via International Commission on Illumination’s L*a*b* color space, Fourier transform infrared spectroscopy, scanning electron microscope, color fastness to washing, rubbing, perspiration and light.

The results obtained indicate extraction with ethanol 90% with a solid/liquid ratio of 1:5 within 1 h, and coloration with a liquor ratio of 1:5 (pH 5) within 2 h under padding pressure of 0.3 MPa are the most effective for coloring worsted fabric.

The C. odorata’s application as a highly effective dyestuff possessing good colorimetric effectiveness has expanded this herb's economic potential, contributing partly to economic growth and adding value to wool in global supply chain.

C. odorata dyestuff has prevailed over other natural colorants because of its impressive color fastness against washing, rubbing, perspiration and especially color stability for pH change.

This paper aims to report on production of the colour digital printing toners cyan, magenta and yellow. Colour digital electrophotographic printing is currently in high demand. The provision of a large colour gamut depends on appropriate selection of precise colourants to produce toner capable of producing a thin layer on paper.

Printing toners were synthesised by the emulsion aggregation method, and then evaluated for chemical constitution and effects of the colourant substituents.

Results demonstrated that increasing the polarity of a pigment produced better dispersion and lower particle size with narrower distribution and even better colour reproduction. While, changing a pigment’s characteristics did not affect the toner shape or its thermal properties.

The developed method provides a simple way to synthesise colour printing toner.

Emulsion aggregation toners provide less hazardous materials during printing.

Evaluations of the influence of solid-state parameters and physicochemical properties of the pigments on printing toner characteristics were done for the first time.

This study aimed at the addition of grape residue flours in beef meatballs to evaluate their behavior on physic-chemical and sensory properties. Furthermore, it is intended to discuss the importance of the substitution of synthetic additives with natural ones, the enhancement of consumers' diets and the prevention of inappropriate waste disposal.

The grapes' residues were collected from wine production and transformed into flour. Their proximal chemical composition and antioxidant activities were analyzed. Then, meatballs were formulated with 0 (control), 3.5 and 7% grape flours. Lipid oxidation analyzes were performed on raw and thermally processed meatballs. Triangle and ranking sensory tests were performed to assess the consumer's perception of product appearance and flavor and the consumer's preference, respectively.

Bordeaux and Trebbiano grape flours were rich in dietary fibers, composed of 44.2 and 55.6% fibers, respectively. They showed a high antioxidant activity, in which Trebbiano was high than Bordeaux. The addition of grape flours reduced the lipid oxidation of meatballs by close to 50% than the control sample. Differences in the appearance and flavor of some meatballs were identified by the panelists; however, the flavor's change did not displease them.

The grape residue is rich in phenolic compounds, natural dyes and dietary fibers. Its addition as a functional ingredient in meatballs reduces the addition of synthetic additives, adds fiber to the consumer's diet and prevents inappropriate waste disposal.

The purpose of this study was to optimise the dyeing conditions to achieve right-first-time dyeing in hard water. Owing to the persistent water scarcity for more than two decades now, the textile industry in Pakistan is forced to rely on high-mineral-content ground water for use in textile wet processing. Furthermore, the limited amount of municipal water that is at the disposal of the textile industry is also high in mineral content. Thus, on the large scale, water hardness has become an acute problem for the textile processor. In particular, in the dyeing process, water hardness is known to have crucial effects. However, to-date, no systematic study has been conducted on this aspect of textile dyeing.

In this study, 3² full factorial design was used to optimise the dyeing conditions to achieve right-first-time dyeing in hard water. Thus, cotton fabric was dyed with Red Reactive dye (of dyebath concentration at 5, 10 and 15 g/L) in prepared hard water (of hardness at 10, 40 and 70°dH), respectively. Analysis of variance, coefficient of determination (R²) and p-values for the models were used to evaluate the adequacy of the predictive models. The surface plots of the effects were studied to further examine the interactions of two independent variables. Derringer’s desirability function was used to determine the optimum levels of each variable.

Three levels for both independent variables generate second-order polynomial models to predict the colour strength, lightness, red/green, yellow/blue and total colour difference values of dyed cotton. The obtained predictive models point out the considerable influence of both water hardness and dye concentration on right-first-time dyeing.

Such a finding enabled the dye-mill to produce the correct shade at water hardness of 10°dH and 15 g/L dye concentration, without the need for corrective reprocessing.

The purpose of this paper is to synthesise, characterise and find out properties of some new bifunctional dyes bis (monochlorotriazine) using tetrahydrobenzo[b]thiophene systems as the chromophoric moiety, bearing good colour strength, lightfastness, and other favourable properties.

The novel reactive dyes were prepared, containing bis monochlorotriazine as reactive groups. The dye is synthesised by diazotization and coupling reactions. Firstly the authors synthesised the ethyl 2‐amino 4,5,6,7‐tetrahydrobenzo[b]thiophen‐3‐carboxylate chromophoric moiety compound which in turn underwent diazotization and coupling then diazotized and coupled reaction with either 1‐amino‐8‐naphthol‐3,6‐disulphonic acid (H‐acid) and or 2‐amino‐8‐naphthol‐6‐sulphonic (γ acid) to give the monoazo dye intermediates compounds. The latter products reacted with 2,4,6‐trichloro‐1,3,5‐triazine in 1:1 molar ratio afforded, via nucleophilic displacement when subjected to condensation 2,4,6‐trichloro‐1,3,5‐triazine in 1:1 molar ratio afforded via nucleophilic displacement, which reacted with 1,4‐phenylenediamine in 2:1 molar ratio to give reaction with the 1,4‐phenylenediamine in 2:1 molar ratio, the bisazobifunctional bismonochlorotriazine reactive dyes.bisazo bifunctional bismonochlorotriazine reactive dyes thus yielding the new target reactive. The synthesised dyes were applied onto cotton fabric under the typical exhaust dyeing conditions and their dyeing properties were investigated.

The results assessed for dyeing indicate high quality dyeing properties However, the homobifunctional (bis MCT) dyes showed higher exhaustion and fixation values, colour yield and fastness properties.

The described method showed the synthesis of bis monochlorotriazines derived from the tetrahydrobenzo[b]thiophene derivative 3 followed by their application towards cotton fabric.

Social implications are to prepare new reactive dyes having higher fastness and uses for dyeing cotton which is the commonest fabric use.

In this work, the novel reactive dyes derived from the tetrahydrobenzo[b]thiophene derivative 3 were synthesized and their structures were based on the analytical and spectral data. Such a group of compounds are considered to be excellent reactive dyes with different colour shades.