Progress in Color, Colorants and Coatings
Volume:17 Issue: 4, Autumn 2024

The research and development of green techniques for the synthesis of silver nanoparticles (AgNPs) with bioactive plants has gained more attention against toxic chemicals. In this research, the aqueous solution of safflower extract was utilized for the simple, green, and commercial synthesis of AgNPs from AgNO3 solution on the wool yarn. The effect of the amount of extract and AgNO3 on the properties of produced nanoparticles was studied. The analysis of AgNPs by Dynamic Light Scattering (DLS) system and Ultraviolet-visible (UV-Vis) spectroscopy exhibited that the particle size of produced NPs was <57 nm. In addition, the colorimetric data of wool yarn dyed with safflower extract in the presence of different concentrations of AgNO3 solution were also studied. The results showed that the presence of nanoparticles changed the color hue (hᵒ: 86→58), and the absorption of safflower extract on the wool samples increased from 5 to 29. Also, the ratings of washing and rubbing fastness of dyed samples were satisfactory (4-5).

This study systematically explores the corrosion inhibition potential of 2-acetylpyrazine for mild steel in a hydrochloric acid (HCl) solution, employing a comprehensive approach that integrates experimental weight loss measurements and Density Functional Theory (DFT) calculations. Investigating inhibitory performance across varying immersion times, inhibitor concentrations, and temperatures, our research aims to elucidate the corrosion inhibition mechanism. Numerical findings highlight a substantial inhibitory efficiency of 92.7 % at an inhibitor concentration of 0.5 mM, an immersion timeof 5 hours, and a temperature of 303 K. Remarkably, the efficiency increases to 98.1 % after extending the immersion time to 48 hours at 303 K with the same inhibitor concentration. Furthermore, we demonstrate the temperature's impact on inhibition efficiency, reaching 97.3 % at 333 K with an immersion time of 5 hours and an inhibitor concentration of 0.5 mM. The Langmuir model, applied to adsorption isotherms, provides valuable insights into the adsorption behavior of 2-acetylpyrazine on mild steel surfaces. Additionally, scanning electron microscope (SEM) results indicate the formation of a protective film on the steel surface in the presence of the studied inhibitors. This combined experimental and computational approach not only enhances our comprehension of the corrosion inhibition mechanism but also emphasizes the practical viability of 2-acetylpyrazine as an effective and temperature-sensitive inhibitor in HCl environments. These findings contribute significantly to advancing corrosion mitigation strategies with potential implications for industrial applications.

Synthetic dyes have gained much of the textile dyeing market by offering various colors. Synthetic dyes have been a worry for the environment owing to their hazardous nature running in parallel. In recent decades, there has been a movement to substitute natural compounds due to their biocompatibility, biodegradability, and biological advantages. This study investigated using Millettia Laurentii sawdust as a natural colorant source. Eco-friendly metal salts (aluminium sulfate, ferrous sulfate, and copper sulfate) under ecologically permitted concentration levels and biomordants (tannic acid, pine bark, oak fruit hull, and eucalyptus leaves) were used to broaden the color range (CIEL*a*b*C*ho and K/S) with significant improvements in the fastness attributes (washing, rubbing, and light) and UV protection properties. Fastness results were found in the commercially acceptable range. All the metal salts provided enhanced color yields with a maximum performance by iron and the corresponding iron-biomordant combinations (iron/pine bark and iron/oak fruit hull). Among the biomordants, pine bark extract provided better performance and higher color depth (9.16) than other biomordants. The findings of this research work showed a significant influence of metal salts and biomordants in combination with Millettia Laurentii sawdust (supposed to be a waste) for enhancing the color characteristics and functional attributes of wool yarns.

Bright print images help any product on the shelf stand out, attract the consumer, and add a unique value to the product. This research work is to empirically identify significant factors and optimize printing press parameters like press speed (x1: 5000, 7000, and 9000 sheets per hour), ink viscosity (x2: 15, 25, 35 Pa·s), and blanket rubber hardness (x3: 65, 70 and 75 shore A) to achieve prints with rich chroma yet with low dot gain in the lithography process, the most economical and widely used process today in the field of label and packaging industry. The parameters used during the printing process can affect the physical dot gain and the color of printed images. To study this, measurements were taken of the dot gain (y1) and color (measured in terms of lightness (y2) and chroma (y3)) at three different dot areas - highlight (25 %), middle tone (50 %), and shadow (75 %). Box-Behnken Design was used to test fifteen different print conditions. The second-order polynomial model's fit quality was good concerning the responses. The optimum printing machine conditions determined to minimize dot gain and lightness and maximize chroma were a press speed of 5000 sheets per hour, 30 Pa·s ink viscosity, and blanket rubber having 70 A shore hardness. The optimized values agreed with the predicted responses were acceptable, considering the right balance of minimum dot gain, higher chroma, and lower lightness to give the vibrant yet controlled halftone dot area in print production.

The present study aims to explore the impact of different types of powder on the latex dispersibility index and pigment binding capacity in Acrylic-Styrene latexes. The methodology employed in this study involves investigating the latex dispersibility index by monitoring the Brookfield viscosity of pre-wetted powder when added to latex. Furthermore, the pigment binding capacity of the powders was evaluated through the wet scrub resistance of the latex paint. The findings from this study emphasize the importance of the size, shape, hydrophobicity, and hydrophilicity of powders in influencing the dispersibility of latex. Additionally, the physical and chemical properties of the powder also influence the binding strength between the powder and latex in the dried film. The implications of this study are discussed in terms of the ability to predict the powder-latex dispersion behavior using the viscosity-latex content curve for each type of powder. The results revealed that the maximum viscosity for the latex mixtures containing talc powder and calcium carbonate occurs at the amount of latex lower than 5 g. In contrast, the mixtures with titanium dioxide powder reach their maximum viscosity in the presence of higher than 10 g latex. Overall, this paper provides valuable insights into the characteristics of powders and their impact on the latex dispersibility index and pigment binding capacity in Acrylic-Styrene-based latexes.