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This paper aims to analyse the tack stability measurement readings of thermochromic offset inks. For this purpose, three reversible leuco-dye formed thermochromic inks were used to evaluate their tack. The used inks differ in their activation temperature, colour, drying mechanism, viscosity and chemical content. Thermochromic offset inks differ from conventional inks in formulation and size of colourants due to the presence of the microcapsules.

Printing inks in offset lithography must have sufficient tack so they can be transported from a reservoir onto the substrate. The ink transfer takes place through the ink splitting by inking rollers, printing plate and blanket transport. An IGT Tackoscope device was used to produce the dynamic readings of ink tack as a function of distribution and splitting time. The data can be used for prediction of the ink press stability under controlled settings, such as temperature.

This research explains the temperature and velocity influence on the tack stability measurement readings of thermochromic inks. It also gives an insight of the chemical compounds that dictate the tack measuring reading results.

Development of new printing inks, such as thermochromic printing inks, may affect the printing of different products. The research was conducted due to a lack of available data for the tack of thermochromic inks.

This paper aims to analyse the let-down stability of the binder-free dispersion of non-printing ink grades of carbon black and to assess the screen-printability of the finished inks formulated thereof from these pigment dispersions.

Binder-free pigment dispersions that were prepared and optimised following a ladder series of experiments (reported in a separate study by the authors) were let-down with three different binders such that inks containing various amounts of a binder were prepared followed by a rheological characterisation immediately after formulation and after four weeks of storage. The screen printability of the inks that displayed considerable stability was assessed, so was the ink film integrity.

The pigment dispersions that were considered in the present study were generally found to be stable after let-down with different binders. This was indicated by the fact that the finished inks possessed a shear thinning viscosity profiles, after formulation and after storage, in most of the cases. Furthermore, the screen printability of the inks was also found to be good in terms of registration quality of a selected design. The structure of the ink film deposits on uncoated and binder-coated textile fabrics was also highly integrated and free from discontinuities.

Carbon blacks with very low volatile matter content and/or high surface area are generally not considered suitable for use in the formulation of printing inks. This is because of their generally poor dispersability and inability to form dispersions that remain stable over extended periods. This work, which is a part of a larger study by the authors, concerns with the stability of inks formulated from binder-free dispersions of such non-printing ink grades of carbon black. The major advantage of using such pigments in inks is that the required functionality is achieved at considerably low pigment loadings.

This study aims to investigate the influence of commercially available resins in water-based magenta pigment inkjet ink formulations on the properties of ink printability and the characteristics of ink application in food packaging. The impact of the resin on the jettability of the existing printability phase diagrams was also assessed.

Inks with different resin loadings were tested for selected properties, such as viscosity, particle size and surface tension. Stability was determined using a Turbiscan AGS turbidimeter and LumiFuge photocentrifuge analyzer. The ink layer fastness against abrasion and foodstuffs was evaluated using an Ugra device and according to PN-EN 646, respectively. JetXpert was used to assess Ricoh printhead jetting performance.

Printability diagrams successfully characterized the jettability of polyurethane inkjet inks on a multi-nozzle printhead and the binder improved droplet formation and printing precision.

Magenta water-based inkjet inks with commercial resins have been developed for printing on paper substrates. To the best of the authors’ knowledge, for the first time, inkjet ink stability was evaluated using the Turbiscan AGS and LumiFuge analyzers, and jettability models were verified using an industrial multi-nozzle printhead.

The present research aims to manage the formulations of pigment-based inks containing aminopropyl/vinyl/silsesquioxane (APSV) as a pigment binding agent for inkjet printing of polyester as a commercial trial for the printing of polyester as a single-step process.

The proposed formulations incorporated APSV by using the mini-emulsion technique at a low relieving temperature under the thermal initiation or UV radiation of vinyl-terminated groups in APSV. In this study, the storage stability of inks with regard to physical properties was broadly examined. Moreover, the color performance, including colorimetric data, color fixation and fastness properties of printed fabrics was evaluated.

The results indicated that the inks containing APSV were formulated and were stable in terms of particle size, dispersion stability, surface tension and viscosity over a period of one month and for four freeze/thaw cycles. APSV successfully fixed the pigment-based inkjet inks on polyester fabric and could achieve a significantly higher color performance and degree of fixation than the formulated inks without APSV.

It could also fulfill all the physical properties of ink prerequisites over storing and eliminating all challenges in improving the performance and utilization of inkjet printing.

APSV can also be used as a pigment binding agent to formulate inks for inkjet printing of polyester fabrics as the authors’ past examination for inkjet printing of polyester fabrics post-treated with APSV.

This study eliminates the noteworthy challenges in formulating the pigment-based inks for textile applications by incorporation of a binder while keeping up the necessary viscosity profile for a specific print head.

This study addressed all the issues arising from the complex nature and very challenging requirements of inkjet inks.

Recent years have seen a significant increase in the use of inkjet technology for printing on textile fabrics. Typical inkjet printed textile products included curtains, large advertising posters, flags and banners. As a result of the need for such inkjet printed products to have a greater durability, especially for outdoor applications, inks containing pigments as the colourants are gaining more interests. However, pigments may give rise to logistical problems in terms of their dispersion stability within the ink formulation, consequently blocking the nozzles within the inkjet print head. This paper reports methods for the preparation of pigment dispersions and of inkjet printing ink formulations and the methods for the evaluation of the suitability of pigmented ink formulations for jet printing on textile materials. In particular, the suitability of three magenta pigments for inkjet inks were assessed and reported.

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.

A disperse fluorescent yellow paste was mixed with a dispersant naphthalene sulfonic derivative via wet grinding process to prepare thermal transfer ink with good fluorescence. The paper aims to discuss these issues.

The surface tension, viscosity, pH value, zeta potential, stability and the morphology of ink samples were tested after the storing process.

The morphology of paste was homogeneous nearly spherical nanoparticles and the particle size was about 100 nm from the transmission electron microscopy (TEM), which was similar to the average particle size obtained from the particle size analyser.

The paste particle size was 126.8 nm after storing at 50°C for one week. The addition of diethylene glycol was conducive to high fluorescent reflectivity and gave good line image quality both in warp and weft directions due to the low viscosity. Inkjet printed polyester fabrics achieved excellent rubbing, laundering and thermal subliming fastnesses.

The polyester fabrics thermal transferred with the ink contained diethylene glycol represented higher fluorescent reflectivity and gave better line image quality both in warp and weft directions. The inkjet printed polyester fabrics showed excellent colour reproducibility and all the fastnesses, including rubbing, laundering and thermal subliming, were higher than Grade 4.

The trend towards a greater use of water as the solvent in flexographic and gravure printing inks has been influenced by a number of factors — the growing attention to environmental pollution problems, health and safety aspects, elimination of residual print odour in food packaging printing and conservation of organic solvents.

The purpose of this study is to prepare thermal transfer ribbons with good alcohol resistance.

A variety of alcohol-resistant thermal transfer inks were prepared using different polyester resins. The printing temperature, printing effect, adhesion and alcohol resistance of the inks on the label were studied to determine the feasibility of using the ink for manufacturing thermal transfer ribbons. The ink formulations were prepared by a simple and stable grinding technology, and then use mature coating technology to make the ink into a thermal transfer ribbon.

The results show that the thermal transfer ink has good scratch resistance, good alcohol resistance and low printing temperature when the three resins coexist. Notably, the performance of the ribbon produced by 500 mesh anilox roller was better than that of other meshes. Specifically, the ink on the matte silver polyethylene terephthalate (PET) label surface was wiped with a cotton cloth soaked in isopropyl alcohol under 500 g of pressure. After 50 wiping cycles, the ink remained intact.

The proposed method not only ensures good alcohol resistance but also has lower printing temperature and wider label applicability. Therefore, it can effectively reduce the loss of printhead and reduce production costs, because of the low printing temperature.

This paper describes a study into the development of an optimum fabrication process for the batch production of thick film titanium oxide‐PVC pH electrodes. Multi‐factorial experimental plans are used to explore the effect of fabrication parameters on the average sensitivity of sensors and their batch variability. Analysis of the results indicates that a number of the factors have a small effect on the sensitivity. Factors of particular importance are identified and TiO₂ in a PVC binder is examined in detail. The optimal values for these fabrication values are identified and examined. Mechanisms for the experimentally observed sub‐Nernstian responses and immersion‐time variations in sensor behaviour are discussed.