Search results

The aim of this study was to evaluate the feasibility of pad printing for producing electrical conductors and to define the factors affecting the print quality of polymeric silver ink conductors.

Polyethylene terephthalate (PET) film and polyphenylene oxide (PPO) compound film were used as substrate materials. Three different polymeric silver inks, marked A, B and C, were used and tested.

The results indicated that the important factors in the pad printing of silver ink conductors are the printing parameters and characteristics of the ink, pad, cliché and substrate. The interactions of these factors should be considered on a case-by-case basis. The sheet resistances of triple-pressed ink conductors varied between 20 and 110 mΩ/sq for 5.7- to 8.5-μm-thick conductors. Ink (B) had a higher sheet resistance than Ink (A) because of its lower silver particle content but also because of the shorter curing time and lower curing temperature. Ink (A) showed excellent adhesion on PET, and Ink (B) had moderate adhesion on PET without corona or plasma pre-treatments, but both inks adhered weakly on PPO compound. Both corona and plasma treatments raised adhesion of these two inks on all test substrates to the highest classification value, 5B.

This paper contains a survey and preliminary testing of the pad printing of polymeric silver ink conductors on flexible thermoplastic foils. Finally, the paper introduces the advantages and drawbacks of the technique.

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.

The surface energy of the printing material can be increased to desired levels with different chemicals or methods. However, the important thing is that the surface properties of printing material are not affected negatively. In this way the aim of this paper provide that the surface properties of matte and glossy coated paper is improved by the argon containing atmospheric pressure plasma device because the plasma treatment method does not occur surface damaging on the papers.

In experimental studies, test samples cut from 160 mm × 30 mm in size from 115 g/m² gloss- and matt-coated papers were used. The plasma treatments of paper samples were carried out with an argon containing atmospheric pressure plasma device of laboratory scale that produces plasma of the corona discharge type at radio frequency. The optimized plasma parameters were at a frequency of 20 kHz and plasma power 200 W. A copper electrode of length 12 cm and diameter 2.5 mm was placed in the centre of the nozzle.

Research findings showed that the surface energies of the papers increased with the increase in plasma application time. While the contact angle of the untreated glossy paper is 82.2, 8 second plasma applied G3 sample showed 54 contact angle value. Similarly, the contact angle of the base paper of matt coated is 91.1, while M3 is reduced to 60.4 contact angles by the increasing plasma time.

Plasma treatment has shown that no chemical coating is needed to increase the wettability of the paper surface by reducing the contact angle between the paper and the water droplet. In addition, the surface energies of all papers treated by argon gas containing atmospheric pressure plasma, increased. Plasma treatment provides to improve both the wettability of the paper and the adhesion property required for the ink, with an environmentally friendly approach.

The purpose of this study is to reveal the usability of waste paper sludge on the production of composite materials and the printability of their surfaces were investigated.

First, composite plates were produced by using dried and milled waste sludge together with polyester resin and epoxy. Screen printing using water, solvent and UV-based inks were carried out.

It was determined that UV and solvent-based inks in both resin groups were permanently attached to the surface of composite plates produced using paper mill waste sludge, while it was found that the adhesion was not achieved sufficiently in cardboard factory waste sludge.

The unique aspect of this study is obtained the composite plates from paper mill and cardboard mill waste sludge and improved the printability of them.

Coates have been manufacturing inks for more than 100 years. In addition to supplying inks for traditional applications such as newspapers and magazines the business involves products for textile printing, flexible packaging, cartons and metal cans. In spite of this wide area of application, there are still relatively few good scientific explanations for the behaviour of printing inks. Quality control tests have traditionally been comparative, non‐quantified procedures, both for raw materials and for finished products. We are introducing IR testing as a guide to the quality of raw materials delivered, but the differences between acceptable and unacceptable materials are not necessarily obvious by IR spectroscopy and this is an area which we have under review.

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 study aims to examine the colour changes affecting inkjet prints after the recycling of papers.

For recycling, papers prepared with the INGEDE 11p standard are recycled four times. Pulping, storage, flotation, beating and bleaching processes are applied for each recycling, respectively. Inkjet prints are made on the obtained test papers, and colour measurements are made using an X-Rite eXact spectrophotometer according to the ISO 13655:2017 standard. These processes are applied again to the papers which are recycled four times, and the results are analyzed. In addition, the values of ΔE₀₀ ′, ΔL′, ΔH ′ and ΔC′ are calculated according to ISO 11664-6:2014 standard by making some calculations according to obtained the L′a′b′ values.

It is determined that the ΔE₀₀ value increases after each recycling in cyan magenta and yellow colour, whereas it decreases in black. The highest ΔE₀₀ value is calculated after the fourth recycling stage is yellow with a value of 8.33. The lowest ΔE₀₀ value detected is black with a value of 0.76 after the fourth recycling stage. This paper observes that the colour with the most variation in hue angle among recycling repetitions is black and the colour with the highest hue angle value is yellow. It is seen that repeating recycling causes increase in the chromatic values of the prints.

After the fourth recycling stage, colour changes have reached an important point and can cause important printing problems. In this case, the customer’s approval must be obtained to continue printing. This case is valid for ΔE₀₀ values. Colour differences for print contrast, trapping and print chroma values are either not very important or are positive for quality.

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.

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.

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.

This study focuses on the preparation of new water-based copolymer nanoparticles and their use as eco-friendly binders for flexographic ink industry.

The ink formulations developed could find use in industrial-scale printing.

Eco-friendly environment ink formulations for printing on paper substrates are novel.

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.

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.

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.

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.

The ink formulations developed could find use in industrial-scale printing.

Eco-friendly environment and low-cost ink formulations for printing on paper substrates are novel.