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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 the physico-chemical, microbiological, colorimetric, sensorial characterization of choris, a traditional smoked pork sausage produced in the state of Goa (India), including its storage stability (0–180 days) at room temperature, aiming at the geographical indication certification and entrepreneurship prospects.

A total of 48 samples of “choris” were collected from 24 villages of Goa and were analyzed at different intervals (0–180 days) for physico-chemical, proximate, microbiological, colorimetric and sensory attributes during the storage at room temperature.

The mean pH of 4.45 and water activity (a_w) of 0.78 were recorded. The pH, tyrosine value, fat percentage and free fatty acid content registered a significant increase, whereas moisture content, a_w and moisture–protein ratio reduced as storage progresses. The colorimetric values lightness (L*), hue angle (H*) and redness index values reduced significantly during storage. The mean total viable count, yeast and mold, and lactic acid bacteria count were found to proliferate significantly as storage advanced. Nevertheless, the hedonic scores not reaching an unacceptable level (= 4) at the end of the storage period.

In accordance with the various parameters adopted during the study, choris could be characterized as “naturally fermented dry smoked” sausages, which were shelf-stable at room temperature for 180 days. The product characterization of choris is essential to guarantee the genuineness, safety and consumer's acceptability. This study will also rebound in an augmented uniformity of the product, which will favor the geographical indication certification and the entrepreneurship prospects of this traditional product.

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.

Our previous papers (Viková & Vik, 2005) described a unique device, now patented in the Czech Republic in the author's name, for photochromic measurement in a reflectance mode together with a methodology. This device allows photochromic sensors to test the colorimetric and spectral characteristics of photochromic textiles, and also fatigue tests for control of colour change stability. This concept of colorimetric and spectral parameters also finds the dependence of colour change on the intensity of UV irradiation and temperature. In this paper, we would like to describe the dependence of colour change on temperature for the photochromic Photopia AQ Ink system (Blue, Purple and Yellow) produced by Matsui Shikiso Chemical Co.Ltd.

It is known that the reversion of photochromic compounds from coloured to colourless is promoted thermally. The photochromic structure can achieve a lower level of saturated absorbance at higher temperatures when thermo reversible photochromic systems, such as spirooxazines and chromenes, increase the rate of thermal bleaching reaction and thus decrease light stimulated coloration.

In this article, a unique concept for a device that conducts photochromic measurement in the reflectance mode together with the methodology described has been patented in the Czech Republic in the author's name. This unique device allows measurements of colorimetric and spectral characteristics of photochromic textiles as photochromic sensors and also as a fatigue tester for the control of color change stability. The measurement of colorimetric and spectral parameters in comparison together with the intensity of UV irradiation allows the dependence of color change on intensity of irradiation to determined, and a scale for individual visual observation to be developed, as well as the risks of UV irradiation to be evaluated.

Inorganic pigments have been widely investigated due to their chemical stability such as resistance to chemical attacks by acids and alkalis, excellent hardness and high temperature stability. Cr_1.3Fe_0.7O₃ which is considered as a ceramic nanopigment also seems to be a highly efficient photovoltaic material. The paper aims to discuss these issues.

In this work, the paper reports the synthesis of a novel and high purity Cr_1.3Fe_0.7O₃ nanopigment via sol-gel process using stearic acid as complexing agent. The method includes formation of an organic precursor with metallic cations homogeneously distributed all over the matrix. Sample characterisations were performed by X-ray diffraction, electron microscopy, UV-vis diffused reflectance spectra and photoluminescence. The transport properties and colour characteristics were also investigated by spectroscopic and technological characterisation of the synthesised nanoparticles.

The prepared nanopigments were uniform in distribution and a spherical morphology with an average size of about 200 nm was observed. Cr_1.3Fe_0.7O₃ nanoparticles showed a direct band gap value of 2.85 eV and the colour efficiency of the nanopigments evaluated by colourimetric analysis resulted characteristic values of L*=39.96, a*=3.67 and b*=3.12.

This method for synthesis of nanopigments is novel and could be employed for various applications in synthesis of wide variety of nanoceramics.

The purpose of this paper is to obtain ZnO‐SiO₂ oxide composites of low bulk density, high homogeneity and consisting of the smallest possible particles. The optimum parameters of precipitation of ZnO‐SiO₂ oxide composites impregnated with natural latex rubber were established. The formation and impregnation the ZnO‐SiO₂ oxide composites were made to occur simultaneously.

The influence of non‐ionic surfactants added during the precipitation process on the physico‐chemical properties of the oxide systems obtained was investigated. The products were characterised by determination of bulk density, absorption capacities of water and paraffin oil, particle size distribution (applying NIBS and laser diffraction methods), as well as SEM observations of surface morphology and microstructure. Moreover, the colorimetric characteristics of the oxide composites obtained and sedimentation profiles in water were analysed. Energo‐dispersive microanalysis of the products enabled determination of the content of ZnO and SiO₂. The surface area (BET) and the size and volume of pores were also estimated.

Modification of the oxide composites with nonylphenylpolyoxyethyleneglycol ethers was found to improve the basic physico‐chemical parameters of the ZnO‐SiO₂ hybrid systems and to change the character of its surface to become more hydrophobic. The conditions in which samples with the best properties were obtained were concluded to be optimum.

Only the selected non‐ionic surfactants were applied as modifying agents of ZnO‐SiO₂.

There is a possible application of ZnO‐SiO₂ oxide composites as activators of rubber compounds and barrier materials in textiles.

The proposed method of ZnO‐SiO₂ oxide composite synthesis in the process of precipitation with simultaneous modification with non‐ionic surfactants provides products with desirable dispersive‐morphological parameters and a hydrophobic surface character.

The purpose of this paper is to investigate the ability of the computer vision system (CVS) to evaluate the colour of poultry meat. The advantages of the CVS over traditional methods were also explored.

The research was carried out on m. pectoralis major samples of three animals for each of the following four species: chicken, turkey, duck and goose. The total colour difference (ΔE) and the degree of difference of hue, chroma and lightness between the methods were calculated. In addition, a trained panel of 14 people was used to carry out three different similarity tests analysed using χ² one sample test and one-way ANOVA. The correlation coefficient between CVS and colourimeter measures was evaluated using the Spearman rank correlation test.

The total colour difference (ΔE) between the methods employed was so large that the generated colour(s) could be considered more opposite than similar. The CVS-generated colour chips were more similar to the sample of the meat products visualised on the monitor compared to colourimeter-generated colour chips in all (100 per cent) individual trials performed. The use of the colourimeter for colour evaluation of lighter coloured poultry meat (chicken and turkey) was unrepresentative.

In this study, a CVS was developed to measure the colour of poultry meat as an alternative to conventional colourimeters.

The research has demonstrated that the use of a CVS should be considered a superior alternative to the traditional method for measuring colour of chicken, turkey, duck and goose meat.

The purpose of this paper is to explore a new eco-friendly green textile dyeing. Natural plant Buddleja officinalis is traditionally used as yellow pigment addition in rice. It is worth developing its application and dyeing performance in cotton fabric.

Buddleja officinalis dried flower was extracted with ethanol aqueous. The extraction conditions including ethanol concentration, material to liquor ratio, extract time and temperature were optimized. Then cotton fabrics were dyed with Buddleja officinalis extraction under conventional and ultrasonic conditions. The effects of dyeing time, bath ratio, pH value of dyeing bath, dyeing temperature and mordants on K/S values were studied and the resulting color strength obtained by conventional and ultrasonic dyeing were compared. The ultraviolet (UV) transmittance of Buddleja officinalis dyed cotton fabric was also evaluated.

The color strength of the fabric dyed with Buddleja officinalis under ultrasonic conditions was higher than that under conventional conditions. Alum, Fe and Cu as simultaneous mordants improved the K/S value of the dyed cotton fabrics. Both washing fastness and rubbing fastness were fairly good in all Buddleja officinalis dyed cotton fabrics, washing fastness = 3–4 and rubbing fastness = 4. What’s more, the dyed cotton fabrics showed lower transmittance values as compared to undyed cotton fabrics and indicated potential UV protection capability.

Buddleja officinalis can be a new natural dye source for the ultrasonic dyeing of cotton fabric.

It is for the first time that Buddleja officinalis is used as a natural dye in cotton fabric dyeing with less water and the dyeing using ultrasound has been found to have an obvious improvement in the color strength and color-fastness.

Natural colorants are believed to be safe because of their nontoxic, noncarcinogenic and biodegradable nature, and also, the demand for natural dyes is steadily increasing. This study aims to investigate the dyeing of polyethylene terephthalate (PET) fabrics under cold plasma and ultraviolet (UV) radiation conditions with Prangos ferulacea.

In the first, some PET fabrics were modified using UV radiation and some others by cold plasma (oxygen/argon), and then the dyeing of fabrics with the natural dye was done (100°C/130°C) without using metallic mordant. Dyeability (color strengths) of the treated samples, colorfastness to washing, light and rubbing, water absorption time, crease recovery angle, air permeability and mechanical behavior were investigated.

The maximum color strength (k/s = 4.87) was achieved for the fabric exposed to UV radiation for 2 h and then dyed with Prangos ferulacea at 130 °C. The results indicated that the dyed fabric showed acceptable colorfastness (very good–excellent) properties in washing and rubbing fastness except for colorfastness to light (moderate). The strength and the angle of crease recovery of treated and dyed samples have increased, while the time of water absorption and air permeability have decreased.

The surface modification of PET (UV radiation and plasma treatment) provides a new idea to improve the dyeability of PET with Prangos ferulacea natural dye without using metallic mordant.