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Printing toners are polymer composites accountable for transmission of digital images onto target substrates. Bearing in mind the ever increasing demand for high quality digital printing, modification and/or integration of existing techniques for manufacturing toners with favourable morphological and colour characteristics appears of vital importance. The present study aims to uncover the significance of in-situ polymerisation method, i.e. suspension, emulsion and mini-emulsion to control the microstructure of toner particles (particle size, particle size distribution and sphereness) while keeping the energy required for polymerisation along with reaction conversion at a reasonable level.

Assessment of particle size, particle size distribution and reaction conversion visualised the potential of suspension, emulsion and mini-emulsion polymerisation techniques to control microstructure, and colour characteristics of synthesized toners as well.

The results provided support for the fact that either the emulsion or mini-emulsion polymerisation routes will result in toners having an acceptable particle size and particle size distribution in the presence of a redox precursor. The higher monomer conversion at low temperature, as compared to the suspension polymerisation, was noticeable.

Analysing the glass transition temperature and colour characteristics of the resulting toners elucidated the superiority of mini-emulsion with respect to the other two cases which ranks this method on account of application.

For the first time, mini-emulsion route was put into practice and toners with acceptable colour and microstructure features were synthesised. In spite of lower polymerisation temperature and higher conversion of mini-emulsion compared to suspension and emulsion polymerisation techniques, further investigations are required to fine-tuning the properties of toners produced through this method.

Toner is a crucial dry colorant composite used in printing based on the electrophotographic process. The quality of printed images is greatly influenced by the toner production method and material formulation. Chemically in situ polymerization methods are currently preferred. This paper aims to optimize the characteristics of a composite produced through emulsion polymerization using common raw materials for electrophotographic toner production.

Emulsion polymerization provides the possibility to optimize the physical and color properties of the final products. Response surface methodology (RSM) was used to optimize variables affecting particle size (PS), PS distribution (PSD), glass transition temperature (T_g°C), color properties (ΔE) and monomer conversion. Box–Behnken experimental design with three levels of styrene and butyl acrylate monomer ratios, carbon black pigment and sodium dodecyl sulfate surfactant was used for RSM optimization. Additionally, thermogravimetric analysis and surface morphology of composite particles were examined.

The results indicated that colorants with small PS, narrow PSDs, spherical shape morphology, acceptable thermal and color properties and a high percentage of conversion could be easily prepared by optimization of material parameters in this method. The anticipated outcome of the present inquiry holds promise as a guiding beacon toward the realization of electrographic toner of superior quality and exceptional efficacy, a vital factor for streamlined mass production.

To the best of the authors’ knowledge, for the first time, material parameters were evaluated to determine their impact on the characteristics of emulsion polymerized toner composites.

In the current study, the authors prepared conductive nano-structured thin films composed of copper on the surface of the printed paper using a magnetron sputtering system. Furthermore, the printability of conductive films for the sake of re-using printed paper and its additional applications were also investigated.

Paper-based electronic devices have been the matter of intense interest because of their easy accessibility, lightweight, low cost, biodegradable, recyclable and ecofriendliness. Furthermore, these devices are inexpensive compared to other substrates. Nowadays, flexible energy and electronic devices made of the paper substrate are receiving a significant interest because of the issue of sustainable energy production from the environment. One of the most reliable techniques for the deposition of thin films and creating conductive patterns on the paper is magnetron sputtering.

The printed and coated printed papers were evaluated with X-ray powder diffraction, scanning electron microscopy with energy-dispersive (SEM-EDX), four-point probe conductivity and spectroscopic measurements.

The paper investigates the printability of conductive paper attributable to its second application.

The authors prepared conductive nanostructured copper-based thin films on the surface of the printed paper. They recovered and reused the paper as a root of raw material due to the environmental issue.

The purpose of this paper is to investigate the effect of expandable graphite (EG) plates’ incorporation on the mechanical, thermal and fire-retardant properties of an epoxy–aliphatic amine system. In addition, the optimum amount of EG in epoxy/EG composites is determined to achieve the best thermal and mechanical properties at the same time.

The epoxy/EG composites were prepared by using (1-4) phr of EG. The morphological structure of epoxy/EG composites was studied by using scanning electron microscopy. The thermal, flame-retardant and mechanical properties of epoxy/EG composites were evaluated by using thermogravimetric analysis (TGA), oxygen index test and dynamic mechanical analysis and tensile and impact test, respectively.

TGA results showed that the incorporation of EG to the epoxy resin increased the initial decomposition temperature and residue weight of the composites. It was found that, with increasing EG concentration up to 4 phr, the oxygen index, glass transition temperature and Young’s modulus of epoxy/EG composites increased up to 60 per cent, 4.1°C and 50 per cent, respectively. On the other hand, the sample with 2 phr EG provided the maximum values of tensile strength, storage modulus, cross-linking density, ultimate tensile strain and impact strength.

Prepared epoxy/EG composites can be used as halogen-free flame-retardant composites. The proposed process for the preparation of the composites is simple and can easily be implicated in the industry.

To the best of the authors’ knowledge, there is no other publication that considers mechanical, thermal and fire-retardant properties of epoxy/EG composites in one paper. In this work, the optimum concentration of EG in epoxy/EG composites was determined, considering all these properties.

This paper aims to report on production of the colour digital printing toners cyan, magenta and yellow. Colour digital electrophotographic printing is currently in high demand. The provision of a large colour gamut depends on appropriate selection of precise colourants to produce toner capable of producing a thin layer on paper.

Printing toners were synthesised by the emulsion aggregation method, and then evaluated for chemical constitution and effects of the colourant substituents.

Results demonstrated that increasing the polarity of a pigment produced better dispersion and lower particle size with narrower distribution and even better colour reproduction. While, changing a pigment’s characteristics did not affect the toner shape or its thermal properties.

The developed method provides a simple way to synthesise colour printing toner.

Emulsion aggregation toners provide less hazardous materials during printing.

Evaluations of the influence of solid-state parameters and physicochemical properties of the pigments on printing toner characteristics were done for the first time.

This paper aims to investigate the effect of paper properties (whiteness, gloss and roughness) on colour laser printing quality. Paper characteristics have a significant influence on print quality and are crucial variables for predicting and reproducing colour.

Six kinds of paper with different properties were selected and the effects of the paper characteristics on the printed paper were studied. Samples were printed with cyan, magenta and yellow toner with a laser printer under identical conditions. The papers and printed papers were evaluated with atomic force microscope, scanning electron microscope, gloss-meter, spectrophotometer and densitometer.

Results showed that print quality is statistically dependent on paper type, and the average optical density of printed paper varied for different papers. Furthermore, the increase in the roughness and gloss of the papers in comparison to whiteness more significantly affected the optical density of paper by reducing it.

To achieve high-quality print, laser printing paper and toner require controlled characteristics.

For the first time, the present study evaluated the influence of paper properties on the quality of colour laser printing.