Search results
1 – 10 of 968
Abstract
Details
Keywords
Walaa M. Abd El-Gawad and Wael Mohamed Abdelmaksoud
This study aims to investigate the possibility of synthesizing cobalt doped willemite ceramic blue pigment by using Egyptian white sand as environmental and economical raw…
Abstract
Purpose
This study aims to investigate the possibility of synthesizing cobalt doped willemite ceramic blue pigment by using Egyptian white sand as environmental and economical raw material for multi-applications in coatings and inks.
Design/methodology/approach
After the synthesis process, the prepared blue pigment was characterized via X-ray diffraction, scanning electron microscopy and energy-dispersive X-ray analysis technique. Then the blue pigment was integrated into both coating and ink formulations. The effect of the prepared multifunctional coatings on corrosion resistance and thermal stability was evaluated using different standard tests. Also, the effect of inclusion of blue pigment in flexographic printing ink formulation was done.
Findings
The results showed that the coating containing the cobalt doped willemite blue pigment offered good anticorrosive performance and high thermal stability. Additionally, the presented results revealed that integration of the blue pigment in flexographic printing ink formulation enhanced fineness, gloss, viscosity and color more than the commercial one “FX 430–201.”
Originality/value
In conclusion, relied on the eco-friendly principle which can be regarded as an economic and green strategy, it can be obtained that this new pigment can provide good multifunctions such as corrosion resistance and thermal stability in coatings and good fineness, gloss, viscosity and color in inks which can enable them to be widely applied in different industries.
Details
Keywords
Zhi Guo, Zhongde Shan, Dong Du, Mengmeng Zhao and Milan Zhang
This paper aims to determine how the viscosity and curing agent content affect the flowability of moist silica sand granules. In addition, a coating device was designed according…
Abstract
Purpose
This paper aims to determine how the viscosity and curing agent content affect the flowability of moist silica sand granules. In addition, a coating device was designed according to the flow properties of silica sand granules.
Design/methodology/approach
The flowability of silica sand granules premixed with two curing agents of different viscosities is studied using a Jenike shear apparatus. An open-ended device was used in discharge testing of sand granules with a design based on the variable dip angle of the two plates and variable outlet size.
Findings
The test results show that increasing the curing agent content would significantly decrease the flowability of silica sand granules, and a curing agent of higher viscosity has a greater effect on the flowability of silica sand. The presence of a curing agent strengthens the cohesion among sand granules, lubricates them and restrains their deformation. The shape function of the coating device was obtained by theoretical derivation.
Practical implications
The flow properties provide a valuable theoretical guidance for the design of coating device for sand mold printing.
Originality/value
This paper deals with experimental work on flow properties of silica sand granules with different viscosities and curing agent content. The shape function of a wedge-shaped coating device is obtained based on experimental data.
Details
Keywords
Osama Abdel Hakeim, Asmaa Ahmed Arafa, Magdy Kandil Zahran and Laila Abdel Wahab Abdou
The purpose of this paper is to prepare ultra-violet (UV)-curable inkjet inks for textile printing application. The influence of both type and component ratio of monomer/oligomer…
Abstract
Purpose
The purpose of this paper is to prepare ultra-violet (UV)-curable inkjet inks for textile printing application. The influence of both type and component ratio of monomer/oligomer on the quality of the desired viscosity range is studied. Moreover, the effect of pigment/resin ratio on the rheological behaviour of the ink has been studied.
Design/methodology/approach
Aqueous dispersions of nanoscale organic pigments were prepared through ball milling and ultrasonication. The dispersed pigments were encapsulated into UV-curable resin via miniemulsion technique, using different types and component ratios of monomers and oligomers.
Findings
It was found that the monomer/oligomer ratio of 2:3 and the pigment/resin ratio of 2:1 gave the most stable miniemulsion dispersions and provided the most suitable rheological range for inkjet printing inks.
Research limitations/implications
As the rheology of the ink is optimised, most of the problems associated with the jetting process could be avoided.
Practical implications
This method of using UV-curable encapsulated inks eliminates the usage of binders, which are the principal factor for nozzle clogging of the print head. In addition, binders are responsible for the coarse handle of the printed textiles.
Social implications
The UV-curable inks were viewed as a green technology by the US Environmental Protection Agency.
Originality/value
This method is simple and fast and requires low cost. In addition, it could find numerous applications in surface coating.
Details
Keywords
J. Bax and B.J. Sauntson
Synthetic polymers were first introduced to the wallpaper trade about twenty‐five years ago. Until that time natural polymers, such as casein and starch, were the only suitable…
Abstract
Synthetic polymers were first introduced to the wallpaper trade about twenty‐five years ago. Until that time natural polymers, such as casein and starch, were the only suitable binders available, and it was necessary to insolubilise them with alum or glyoxal in order to afford some degree of water resistance to the prints. The only smear‐proof washable papers were those supercoated with a film of varnish. This varnish supercoat was the first to be replaced by a synthetic polymer emulsion.
H. Abd El-Wahab, G.A. Meligi, M.G. Hassaan and L. Lin
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.
Abstract
Purpose
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.
Design/methodology/approach
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.
Findings
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.
Research limitations/implications
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.
Practical implications
The ink formulations developed could find use in industrial-scale printing.
Originality/value
Eco-friendly environment and low-cost ink formulations for printing on paper substrates are novel.
Details
Keywords
ABM Chemicals Ltd is exhibiting its range of photosensitisers for uv curing including the Glocure benzoin ethers. These highly cost effective materials ensure maximum utilisation…
Abstract
ABM Chemicals Ltd is exhibiting its range of photosensitisers for uv curing including the Glocure benzoin ethers. These highly cost effective materials ensure maximum utilisation of uv energy for the polymerisation process.
H. Abd El-Wahab, G. El-Meligi, M.G. Hassaan, A. Kazlauciunas and Long Lin
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.
Abstract
Purpose
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.
Design/methodology/approach
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.
Findings
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.
Practical implications
This study focuses on the preparation of new water-based copolymer nanoparticles and their use as eco-friendly binders for flexographic ink industry.
Social implications
The ink formulations developed could find use in industrial-scale printing.
Originality/value
Eco-friendly environment ink formulations for printing on paper substrates are novel.
Details
Keywords
The basic reasons for use of an overprint varnish are generally to afford protection to the inks and/or substrate and to promote gloss. The types of coating available can be…
Abstract
The basic reasons for use of an overprint varnish are generally to afford protection to the inks and/or substrate and to promote gloss. The types of coating available can be summarised as follows in approximately an order of increasing gloss level.
Reducing Level of Alcohol in Inks ‐ A medium‐sized US ink manufacturer recently needed to reduce the level of alcohol in its bases for water‐based inks. Ciba Geigy Pigments…
Abstract
Reducing Level of Alcohol in Inks ‐ A medium‐sized US ink manufacturer recently needed to reduce the level of alcohol in its bases for water‐based inks. Ciba Geigy Pigments Division's Inks Technical Centre developed an improved formulation, containing half the alcohol of the previous one and 40 per cent more pigment to allow the ink producer to meet VOC limits and increase production efficiency, at no additional cost.