Ink-jet printing of micro-emulsion TiO2 nano-particles ink on the surface of glass

A self-cleaning ceramic ink that contains nano-titanium dioxide was formulated. The nano-titanium dioxide was generated through the micro-emulsion process. The physical properties such as surface tension and viscosity of the prepared ink were evaluated. The ink-jet printing was carried out with an Epson Stylus Photo P50 printer on microscope glass slides. The print was set to 1, 3 and 5 runs in order to evaluate variations in wettability and resulting self-cleaning properties with varying thicknesses of the printed film. Following initial drying of the printed self-cleaning microscope glass slides; they were heat-treated at 400 °C. The SEM analysis and contact angle measurements of the printed microscope glass slides were carried out. The thicknesses of the raw printed self-cleaning ceramic inks were increased linearly with the number of printing runs. Ultimately, the results demonstrated that the direct ceramic ink-jet printing method can be used to produce a self-cleaning film on the glass.     

Synthesis and evaluation of a novel blue cationic reactive dye for modified nylon 6.6 ‘Tactel Coloursafe’

A novel blue cationic reactive dye (dye 1 ) based on an azo benzothiazole derivative and possessing an acrylamido reactive group, was synthesised and evaluated on dyeing Coloursafe modified nylon 6.6 at optimum pH. Benzothiazole quaternary dye was chosen as a target as this is known to be very strong chromophically. Evaluation of the technical properties of dye 1 showed that it fixed efficiently to nylon under acidic dyeing conditions. As it was necessary to prove that fixation occurs via a covalent bond, the dyeing properties of a non‐reactive cationic dye, (CI Basic Blue 41), on dyeing nylon 6.6 at optimum pH were evaluated. CI Basic Blue 41 was similar in structure to dye 1 and would be capable of forming an ion–ion bond with the fibre. Evaluation of the technical properties of dye 1 proved that, in all cases, its fixation efficiency and build‐up properties were far better than that of CI Basic Blue 41.     

Single‐phase ink‐jet printing onto cotton fabric

The current commercial application of ink‐jet reactive inks to cotton fabrics requires pretreating with pad liquor containing a thickener, urea and alkali prior to printing. In this study, attempts have been made to develop a reactive ink‐jet print in a single‐phase process by adding an organic salt to the ink formulation and hence removing the need to pretreat fabrics. This approach utilises inks containing both a reactive dye, in this case Procion Red H‐E3B, and an organic salt such as sodium formate, sodium acetate, sodium propionate or tri‐sodium citrate. The behaviour of a novel reactive ink formulation for ink‐jet printing on to cotton fabric was evaluated at different pH vlaues. The results at optimum pH indicated that printed non‐pretreated fabrics with ink containing organic salts exhibited a higher level of reactive dye fixation than printed pretreated fabric containing no organic salt ink. The yielded prints demonstrate excellent colour fastness to washing and dry/wet crocking properties. The light fastness of the printed fabrics was improved by adding an organic salt to the ink formulation.     

Synthesis of ZnS–Mn nano-luminescent pigment for ink applications

In the present study, ZnS–Mn nano-luminescent pigments were synthesized, using co-precipitation method. Polyvinylpyrrolidine (PVP) surface modifier and Mn dopant concentrations were considered as affecting parameters. The luminescent ink was loaded with two different concentrations of pigments. The obtained ink was silk-screened on different types of fabrics mainly treated cotton, cotton and nylon. Structure, microstructure, luminescent properties of nano-pigments, inks and fabrics and also rheological properties of the inks were investigated. The results showed that the ceramic ink prepared with nano-luminescent pigment had high photoluminescence (PL) intensity. Moreover, the optimum concentrations of Mn and PVP for obtaining maximum PL intensity were found as 2 and 5 wt%, respectively. SEM images of fabrics indicated that nanoparticles were loaded, nonuniformly, on the fibers. The treated linen and nylon fabrics showed maximum and minimum PL intensity, respectively, due to ink penetration depth in the fabrics. Furthermore, washing fastness estimated for all fabrics was in the proper range.     

Synthesis of polypyrrole/indium tin oxide nanocomposites via miniemulsion polymerization

Polypyrrole/indium tin oxide nanocomposites were synthesized via in situ miniemulsion polymerization of pyrrole monomer in the presence of indium tin oxide nanoparticles. Different nanocomposites were synthesized by different loadings of nano indium tin oxide. The morphology and nanoparticles distribution of the nanocomposites were characterized by electron microscopy. The results of XRD and TEM analysis showed that indium tin oxide nanoparticles were well placed in the polymeric structure of latex. FTIR analysis was used for the characterization of synthesized polypyrrole and its nanocomposites. TGA analysis was performed to investigate the thermal behavior of pristine polypyrrole and its nanocomposites. Conductivities of nanocomposites were measured by 4-point probe method and compared to the neat polymer.     

Encapsulation of flexible organic light emitting diodes by UV-cure epoxy siloxane

In this research, a silicon additive was synthesized by reaction of the hydroxyl terminated poly-dimethyl siloxane (PDMS-OH) with 3-glycidoxy propyl tri-methoxy silane (TMS-epoxy). The synthesized silicon additive characterized and evaluated to use as a curing agent for preparing high-performance and impermeable epoxy resin for encapsulation of flexible optoelectronic devices such as thin film photovoltaics and polymer light-emitting diodes to protect them against water penetration and increase their lifespan. The synthesized additive was characterized by FTIR, NMR, and elemental analysis. Thermal properties of the UV curable resin were investigated by using DSC and DMTA. The prepared UV cure epoxy resin exhibited an appropriate melting temperature (56.19 °C). Contact angle test, SEM, and calcium test was used to investigate the properties of UV-cured coating resin. The water contact angle of the cured prepared resin film showed good hydrophobicity. The SEM results confirmed the uniformity of cured film and UV cure resin dispersion. Transparency and flexibility of the cured film to encapsulate the flexible light emitting diodes are acceptable. The permeability of cured film to water vapor was evaluated by calcium test, which shows the cured film suitability to encapsulate the FOLED. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48033.