H. Abd El-Wahab

Preparation and characterisation of ink formulations for jet printing on nylon carpet

Purpose – The purpose of this paper is to prepare and characterise various ink formulations for inkjet printing on nylon 66 carpet.Design/methodology/approach – Various ink formulations were prepared using CI Acid Red 57, synthetic thickeners (BYK425 and BYK420), ethylene glycol, diethylene glycol, isopropanol with auxiliaries. The inks were characterised for their rheological, wetting and storage stability properties. The inks were jetted using a Printos P16 drop‐on‐demand jet print‐head onto nylon 66 carpet materials. The printed images were characterised using an ImageXpert system.Findings – It is found that the inks containing the synthetic thickeners at the optimum ratio give good printing and image properties, such as optical density, drop size, and depth of penetration into the substrate at pH 4‐5. The optimised ink formulation is found to have good storage stability.Research limitations/implications – The study focuses on ink formulations based on CI Acid Red 57. Ink formulations based on other co...

Synthesis and characterisation of the flame retardant properties and corrosion resistance of Schiff’s base compounds incorporated into organic coating

Purpose – This paper aims to report on the synthesis and characterisation of new flame retardants and anticorrosive additives based on Schiff’s base compounds, which were added physically to organic coating. Design/methodology/approach – Flame retardants are incorporated into polymeric materials either as additives or as reactive materials. Additive-type flame retardants are widely used by incorporating into polymeric materials by physical means. In this research, Schiff’s base (azomethine) compounds are added physically to alkyd paint as flame-retardant additives. Elemental analysis, infrared spectroscopy and proton nuclear magnetic resonance spectroscopy were used to characterise the structure of the prepared Schiff’s base compounds. Thermal gravimetric analysis was used to evaluate their thermal stability. Experimental coatings were manufactured on a laboratory scale, and then applied by brush on wood and steel panels. Findings – Results of an oxygen index value indicated that alkyd paints containing S...

Nano emulsion binders for paper coating synthesis and application

ABSTRACT The key objectives of coating papers and paperboards are to improve their aesthetic appearance and printability. Coatings offer smoothness, gloss, brightness, and opacity to the base papers and provide them with enhanced printability, which requires resistance to ink splitting forces, smoothness, ink holdout and gloss, etc. Styrene acrylate latexes were synthesized, via emulsion polymerization, and were formulated as coats for white and brown recycled papers. Both processes were characterized specifically for offset printing. The prepared latexes showed enhanced solid content, viscosity, zeta potential and appropriate glass transition temperature for paper coating formulation. The porosity, gloss and Cobb60 values of coated papers increased with the increased addition of nano-emulsion modified latexes. The formulations afforded high printability (print gloss and print density) with local ground calcium carbonate compared with that of the imported pigment (kaolin). Furthermore, the synthesized binder had higher water resistance than the commercial one; which can tightly be correlated with print quality, printability and productivity and most significantly, permits usage of low viscous ink. Coated recycled brown base gave promising results with respect to print quality although offset printing was utilized. The novelty of this work was not only in employing the local alternative binder and local pigment but also in achieving compatibility with environmental regulations since oil-based inks and recycled papers were also used.

Synthesis of nanosized mixed metal oxides heat and corrosion resistant pigments: CaMnO3, Ca2Cr2O5 and CaSb2O6

Purpose – The purpose of this paper is to investigate the synthesis of calcium-based group of mixed metal oxide (MMO) pigments. The evaluation of these pigments as heat and corrosion resistant was also explored. Design/methodology/approach – Two simple synthesis techniques, namely, co-precipitation and solid-state calcination method, were used to synthesise nanosized MMO pigments. And then the physico-chemical requirements according to standards for the synthesised pigments are investigated. Findings – The prepared MMO pigments were mainly in the single phase double oxide forms. The prepared oxides exhibited good heat (up to 600°C) and corrosion resistance properties (in 5 per cent NaCl for 500 h). Research limitations/implications – This paper investigates the physico-chemical properties of synthesised calcium-based group of MMO pigments. And then evaluate it as heat and corrosion resistant paints. The simple techniques used for synthesis of nanosized MMO pigments will significantly improve the research ...

Preparation and evaluation of nanosized mixed calcium iron oxide (CaFe2O4) as high heat resistant pigment in paints

Purpose – The purpose of this paper was to prepare and evaluate a nanosized mixed calcium iron oxide as a high heat-resistant pigment. Heat-resistant pigments can be defined as chemical substances that impart color to a substrate or binder and retain their color and finish at elevated temperatures. Mixed metal oxides have been widely used as pigments in coating formulations. Design/methodology/approach – This work presents synthesis of nanosized calcium iron oxide as an inorganic pigment by using simple synthesis technique, namely, solid-state calcination method, to study its heat and corrosion resistance. The prepared pigment was characterized by using X-ray diffraction, infrared spectroscopy, scanning electron microscopy and inductive coupling plasma. It was incorporated into paint formulations, and the heat, corrosion and mechanical resistance of dry paint film was evaluated. Findings – In this work, the prepared calcium iron oxide pigment showed excellent heat and corrosion resistance. Research limita...

Biodegradable polymeric microcapsules for sustained release of riboflavin.

In the current study, a series of polylactic acid and polylactic-co-glycolic acid were prepared in an easy, simple, safe and economically feasible way with yield% greater than 90%. Studying the effect of a catalyst on polymerization process was performed. Riboflavin (RF) was chosen as a model drug and microencapsulated in different (drug: polymer) ratios to modify its performance via o/w emulsion solvent evaporation technique and characterized in terms of the morphology and entrapment efficiency (E.E.) and evaluated via in vitro RF release studies. It has been found that, the release rate consists a burst release at the first 12h, followed by a gradual release over 3days. The cumulative riboflavin release from these microcapsules formulations at the end of 3days was 70% and 80% for PDLA and PDLAGA respectively. The kinetics of release profiles were zero order. The highest (E.E.) of RF obtained among all formulations was 85%.

Effect of short oil‐length alkyd additive on the properties of coal tar binder

Purpose – Demands for coatings with superior technical characteristics have induced the use of composite coatings, which usually represent an extremely strong product. The resin blend technique is a simple and useful method for improving paint properties. Coal tar resins are the most economical coating extensively used in the industry; short oil‐length alkyd resins are usually used for air and force‐dry industrial coatings for metal surfaces. The purpose of this paper is to evaluate coating blends composed of these resins, in particular, the effects of short oil‐length alkyd additive on the properties of coal tar binder.Design/methodology/approach – One way to achieve new types of binders is to make combinations of the existing ones, in an ideal case retaining the desirable properties of both. The alkyd has important properties over the original drying oil. To achieve the goal of improving coal tar resin properties, short oil‐length alkyd was blended with it. The prepared short oil‐length alkyd was charac...

Tailoring of mechanical properties and printability of coated recycled papers

Coated papers have an excessive impact on the appearance and utility of printed materials with respect to the increase in mechanical strength, print gloss and print density. Styrene–butyl acrylate copolymers were synthesized utilizing different emulsifier systems and modified with acrylamide. These lattices were evaluated as paper coats in the presence of kaolin, calcium carbonate and a mixture of both as pigments. The evaluation aimed at employing these lattices on recycled white and brown paper substrates with respect to their mechanical properties and their printability. The tensile strength of coated papers was upgraded by ~ 20–30% in CD compared with that of uncoated papers. The improvement ratio was ~ 12–16% in bursting strength compared with that of the uncoated paper. The maximum gloss values (39 and 48) and the maximum print density values (2.51 and 2.44) were obtained for ground calcium carbonate “GCC” composites on white and brown bases, respectively. Formulas containing GCC had a uniform printed surface with high-quality ink distribution without any picking up of coated surface. This work is a promising one as efficient synthesized binders and a local pigment were employed besides achieving offset printing on recycled brown papers for the first time.