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This paper aims to study the effect of the new modified dispersing agent, milling time of the properties and particle size distribution (PSD) of inkjet ink formulation for polyester fabric printing.

The study’s methods include preparation of different formulations of textile inkjet inks based on different types of dispersing agents, then applying and evaluating the prepared formulations on the polyester fabric. The properties of the prepared ink formulations were analyzed by measuring viscosity, surface tension and particle size. The current work is including the study of the effect of using different doses of different dispersing agents and the milling time on their characteristics. Also, the study was extended to evaluate the printed polyester by using the prepared inks according to light fastness, washing fastness, alkali perspiration fastness and crock fastness.

The results showed that the used dispersing agents and the different milling time enhanced the viscosity and dynamic surface tension in the accepted range, but it was largely cleared in the PSD which tends to perform the inks on the printhead and prevent clogging of nozzles. Light fastness, washing fastness, alkali perspiration fastness and crock fastness gave good results in agreement with this type of inkjet inks for textile printing.

In this work, good results were obtained with this type of dispersing agent for inkjet ink formulations, but for other dispersing agents, other tests could be performed. The inkjet ink could also be formulated with other additives to prevent clogging of nozzles on the printhead.

These ink formulations could be used for printing on polyester fabric by the inkjet printing.

Recently, there was a considerable interest in the study of the effect of PSD on the inkjet inks to prevent clogging of nozzles on the printhead and to improve the print quality on the textile fiber.

This paper aims to clarify the relationship between the slurry erosion and one of the case hardening treatments, i.e. boronizing in this study, for AISI-5117 steel alloy. AISI-5117 steel alloy was used because of its variety applications in the field of submarine equipment. Most of the slurry erosion factors such as velocity, impact angle and mechanism of erosion were studied at different impact angles.

At first, the samples were prepared and subjected to the boronizing treatment in controlled atmosphere. By using a slurry erosion test-rig, all experiments for studying the slurry erosion factors were carried out. Moreover, the studied specimens were investigated via scanning electron microscope, optical microscope and X-ray diffraction to study the erosion mechanism in the different conditions.

It was expected that the boronization of the AISI-5117 steel would increase its slurry erosion resistance due to its positive impact on the surface hardness. However, the results observed show the opposite, where the boronization of AISI-5117 steel decreased its slurry erosion resistance as implied by the increase of the mass loss percentage at all impact angles.

This research, for the first time, exhibits the effect of boronizing treatment on the slurry erosion in different impact factors accompanied by the erosion mechanism at each impact angle.

Fused deposition modeling (FDM) is one of the most adopted additive manufacturing techniques to produce prototypes and/or final parts regardless of geometrical complexity restrictions. One of the most challenging aspects of this technology is the attainable roughness. The purpose of this study is to evaluate the capability of the slurry impacts to improve the surface roughness of parts fabricated using FDM. Moreover, a regression model for predicting the values of surface roughness was developed.

The developed technique imposes a silica–water mixture which softens the staircase on the surface and leaves it smoother. The process introduces three main factors: building orientation; layer thickness; and impact angle of the slurry particles. Experimentally, a test rig was used to evaluate the effect of these factors on surface roughness. Statistically, Analysis of variance (ANOVA) and regression analysis were conducted to study the contribution of the individual factors on the roughness.

The results reveal that the effect of slurry impacts has a good impact on surface roughness, and the three factors have significant effect on surface roughness.

This paper contributes to new knowledge by providing a new technique for enhancing the surface roughness of FDMed products. ANOVA and regression analysis is a useful tool to parametrically study the surface roughness in terms of building and testing factors.

The study aims to assess the efficiency of nanocomposite to improve the properties of gap-filling materials for pottery artifacts.

Five different pastes were used in the laboratory studies. The pastes consist mainly of pottery powder (grog), dental plaster, microballoons and an adhesive of Primal AC33, nano-silica and nano kaolinite in various concentrations. The prepared samples were subjected to accelerated heat and light aging. Besides, some investigations were used to evaluate the efficacy of the additive nanomaterials, such as TEM, digital and scanning electron microscopy microscopes. Contact angle, color change, shrinkage degree, physical properties and compressive strength tests were also conducted.

The results indicated that using Nano-silica considerably improves the mechanical strength and decreases the shrinkage of gap-filling materials. According to the results, a mixture of grog, microballoons and Primal AC33/Nano-silica Nanocomposites is the optimal gap-filling paste for archaeological pottery. Moreover, this paste showed a higher contact angle (120°), lower color change (ΔE = 2.62), lower shrinkage (3.3%), lower water absorption (3.36%), lower porosity (5.05%) and higher compressive strength (5124 N/mm²).

This paper attains to develop an economic polymer-nanocomposite that can be used with gap-filling materials for pottery artifacts.

Paper aims to preparation of new acid disperse dyes based on thiadiazol derivatives and evaluation of their use as antimicrobial colorants in digital transfer-printing ink formulations for printing onto polyester fabric substrates.

New disperse dyes based on 1,3,4 - thiadiazol derivative (dyes 1–3) were prepared and evaluated by different analysis then formulated as colored materials in the ink formulations. The viscosity, dynamic surface tension and particle size distribution of the prepared inks were measured. The printed polyester fabric substrates were tested using a variety of tests, including light fastness, washing, alkali perspiration and Crock fastness, as well as depth of penetration. Density-functional theory (DFT) calculations were carried out at the Becke3-Lee-Yang-parr (B3LYP) level using the 6–311** basis set, and the biological activity of the prepared disperse dyes was investigated.

The obtained results of the physical of the prepared ink revealed that thiadiazol disperse ink is a promising ink formulation for polyester printing and agrees with the quality of the printed polyester fabric. The optimization geometry for molecular structures agreed with the analysis of these compounds. The HOMO/LUMO and energy gap of the studied system were discussed. The molecular docking analysis showed strong interaction with DNA Gyrase and demonstrated to us the high ability of these inks to act as antimicrobial agents.

The prepared inks containing the prepared thiadiazol disperse dye were high-performance and suitable for this type of printing technique, according to the results. The prepared inks resist the growth of microorganisms and thus increase the ink's storage stability.

The prepared disperse dyes based on 1,3,4 - thiadiazol derivative (dyes 1–3) can be a promising colorant in different applications, like some types of paint formulations and as a colorant in printing of different fabric substrates.

This paper aims to synthesize new screen-printing ink formula based on new derivatives of azo thiadiazol disperse dyes and evaluate their characteristics after being printed on polyester fabric substrates.

New dispersed dyes based on 1, 3, 4-Thiadiazole derivatives (dyes 1 and 2) were prepared and confirmed by different analyses, infrared (IR), mass and nuclear magnetic resonance (NMR) spectroscopy, and then formulated as colored materials in the screen-printing ink formulations. Printing pastes containing the prepared dyestuffs and other ingredients were used for printing polyester using screen-printing or traditional printing. The characteristics of printed polyester fabric substrates were measured by color measurements such as a*, b*, L*, C*, E, Ho, R% and color strength, as well as light, washing, crock and alkali perspiration fastness, and finally, the depth of penetration was evaluated.

The prepared 1, 3, 4-Thiadiazole derivatives (dyes 1 and 2) were obtained from the reaction of 5,5’-(1,4-phenylene)bis(1,3,4-Thiadiazole-2-amine) with resorcinol and m-toluidine as a coupling component. The suitability of the prepared dyestuffs for silk screen-printing on polyester fabrics has been investigated. The prints obtained from a formulation containing dye 1 possess high color strength as well as good overall fastness properties if compared to those obtained using dye 2.

The method of synthesis of the new dyestuffs and screen-printing ink provides a simple and practical solution to prepare some new heterocyclic disperse azo dyes, and they are formulated in the screen-printing inks for printing on a polyester fabric substrate.

The prepared disperse dyes based on 1,3,4-Thiadiazole derivatives (dyes 1 and 2) could be used in textile printing of polyester on an industrial scale.

The purpose of this paper is to prepare, characterise and evaluate nano-emulsions of copolymers of various compositions as eco-friendly binders for flexographic ink industry.

Various nano-emulsions of copolymers were prepared using styrene (St), butyl acrylate (BuAc), acrylic acid (AA) and acrylamide (AAm) monomers by means of a conventional seeded emulsion polymerisation technique, using K2S2O8 as the initiator. The characterisation of the prepared emulsions was performed using Fourier transform infrared (FT-IR), thermogravimetric analysis (TGA), gel permeation chromatography (GPC) and transmission electron microscopy (TEM). A selection of copolymers was formulated with pigments and additional ingredients, as water-based flexographic inks. The inks were characterised for their viscosity, pH, degree of dispersion, water resistance and colour density.

It was found that the low viscosity of the prepared copolymers may reduce the film thickness of the flexographic inks and may also increase the spreading of the ink on the surface. As a result, stable modified polyacrylate-based latex with improved physico-mechanical properties were obtained. The prepared latexes were showed improving and enhancing in water resistance; gloss values, and the print density that ranged from 2.06 to 2.51 and the maximum gloss values (39 and 48) were also obtained. Also, these binders provide excellent adhesion properties for both the pigment particles and the base paper.

This study focuses on the preparation of new water-based copolymer nanoparticles and their use as eco-friendly binders for flexographic ink industry.

The ink formulations developed could find use in industrial-scale printing.

Eco-friendly environment ink formulations for printing on paper substrates are novel.

The purpose of this study is to prepare, characterise and evaluate nano-emulsions of ter-polymers of various compositions as eco-friendly binders for flexographic ink industry.

Various nano-emulsions of ter-polymers were prepared based on Vinyl acetate, Vinyl Versatate, butyl acrylate, acrylic acid and acrylamide monomers by means of a conventional seeded emulsion polymerisation technique, using K₂S₂O₈ as the initiator. The characterisation of the prepared emulsions was performed using Fourier transform infrared, thermo-gravimetric analysis, gel permeation chromatography and transmission electron microscopy. A selection of co-polymers and ter-polymers were formulated with pigments and additional ingredients, as water-based flexographic inks. The inks were characterised for their rheological properties, pH, degree of dispersion, water-resistance and colour density.

It was found that the low viscosity of the prepared polymers may reduce the film thickness of the flexographic inks and may also increase the spreading of the ink on the surface. As a result, stable modified poly acrylate-based latex with improved physico-mechanical properties was obtained. The prepared latexes showed improved properties such as enhanced thermal stability and better water resistance. The effect of the emulsifier type on the properties of the resulting emulsion latexes and their corresponding films were investigated. Also, as the hydrophobic monomer increases, so does the colour density and increasing the binder ratio enhances the gloss values. The improving in gloss values were obtained and provide excellent adhesion properties for both the pigment particles and the base paper.

The study focusses on the preparation of new water-based ter-polymer nano-particles and their use as eco-friendly binders for flexographic ink industry. Ink formulations based on other different type emulsion polymers could also be studied to assess the applicability of the ink formulation system found for other binders.

The ink formulations developed could find use in industrial-scale printing.

Eco-friendly environment and low-cost ink formulations for printing on paper substrates are novel.

This study aims to empirically explore telecommunications service quality (SQ) and its impact on the customer loyalty (CL) through a mediating impact of customer satisfaction (CS) during the COVID-19 pandemic crisis.

A survey was conducted involving 384 customers of telecommunications service providers in Egypt. The hypothesized direct relationships were tested through regression analysis, and the mediating effect was tested using structural equation modeling technique.

The results reveal a strong positive relationship of SQ dimensions, CS and CL. Reliability, privacy and security and convenience, respectively, proved to increase CS and CL more than the other SQ dimensions, particularly during COVID-19. Moreover, CS was found to significantly and fully mediate the effect of SQ on CL.

This is an empirical research applied in the Egyptian telecommunications setting. Its relationships need further investigation in other settings and countries. Also, traditional limitations of a cross-sectional study apply with respect to the attribution of causality and the time lag effects.

In strategic planning of telecommunications services and the associated consumer behavior, the results of this study can be helpful for policymakers. In case of similar epidemics and natural calamities, consumers may depict similar behavior as shown during the lockdown and social distancing during COVID-19; hence, this study can help regulatory bodies in preparing their safety roadmap.

This study contributes to the body of knowledge in enhancing the understanding on the impact of telecommunications SQ on CS and loyalty, particularly during the COVID-19 pandemic crisis.

The purpose of this paper is to empirically investigate the relationship between intellectual capital (IC) (i.e. human capital, structural capital, relational capital) and service quality (SQ) within the Egyptian mobile telecommunications setting.

A valid research instrument was utilized to conduct a survey of 384 top- middle- and supervisory level managers from three Egyptian mobile telecommunications companies.

Hypotheses related to the relationship of human, structural and relational capital and their influence on SQ were tested. Results show that Egyptian mobile telecommunications companies have mostly emphasized the use of structural capital to boost their SQ.

This is an empirical research applied in the Egyptian telecommunications setting. Its relationships need further investigation in other settings and countries. Also, the traditional limitations of a cross-sectional study apply with respect to the attribution of causality and the time lag effects.

The optimal procedure for the Egyptian mobile telecommunications companies is to focus their efforts on managing all three components of IC in order to improve their SQ and performance.

This is one of the very few researches to study the relationship between intellectual capital and service quality and the first to investigate these relationships in the Arab Region within the mobile telecommunications setting.