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Even though most information is digitized today, paper as a printing substrate is still essential. The quality of the paper depends on whether it has the properties required for its intended use, which will fundamentally rely on the raw materials used. Nowadays, the production of paper and board is increasingly focused on alternative non-wood raw materials. In this context, the main objective of this research is to improve the quality of prints on laboratory-made papers with supplementary barley pulp by coating the surface of the papers with titanium dioxide coating. Since laboratory-made papers were not subjected to the bleaching process and no additional surface treatments were used, TiO2-based coating proved to be one of the ways to improve the quality of the prints on such substrates. In this study, it was concluded that TiO2-based coating did not affect the colorimetric values of the black prints to the extent that it affected the colorimetric values of the magenta prints. However, density of printed inks was increased up to 14% for prints on laboratory-made papers with higher amount of barley pulp and TiO2-based coating in two layers.

Objectives The development and placement of translucent zirconia ceramics on the dental materials market is in full swing. This research aimed to investigate how aging protocols affect the microstructure, color parameters and translucency of a new-generation monolithic zirconia ceramic. Material and methods Translucent zirconia ceramics KATANA-Zirconia STML with different surface treatments (as sintered - control, glazed, polished) was tested using two aging protocols (hydrothermal degradation in autoclave at 134 °C and 2 bars for three hours, chemical degradation in four-percent acetic acid at 80 °C for 16 hours) in order to examine phase composition using X-ray diffraction analysis and ΔE, ΔL and ΔC color parameters through spectrophotometry. The translucency parameter (TP) was calculated using parameters L*, a* and b* on a black and white surface. Results Regardless of the surface treatment, aging protocols did not cause a tetragonal-to-monoclinic phase transformation, although hydrothermal degradation in the autoclave transformed the hybrid tetragonal-cubic structure of all specimens to a tetragonal one. All polished and glazed specimens during chemical degradation demonstrated a significant color change ΔE. Lightness ΔL significantly changed in polished specimens aged in the autoclave. In all specimens, ΔC underwent a change manifested through statistically insignificant yellowing. None of the aging protocols altered the translucency of specimens. Conclusions Aging, regardless of the final surface treatment, did not manifest a monoclinic phase in the specimens. A tetragonal-cubic microstructure dominates. Unlike polishing, glazing the surface of translucent zirconia ceramics contributed to minor changes in color, lightness and chromaticity. The translucency of translucent zirconia ceramics remains stable regardless of aging and surface treatment.

Purpose This paper aims to highlight the importance of braille for visually impaired people and the possibility of printing it by using the ultra-violet (UV) inkjet printing technique. Design/methodology/approach The vision impairment, definitions and statistics, as well as braille letter and standards, are first reviewed. Then, the methods of printing braille have been discussed, with a focus on UV ink-jet printing. Finally, this study indicates a significant role of UV ink-jet printed Braille, its possibilities and its advantages. Findings Research studies in the field of UV ink-jet printed braille are showing that it is possible to print good legible braille of the adequate height of dots. This paper highlights some advantages of printing braille with UV ink-jet, like the possibility of achieving greater dot height than embossing and no need for printing form. Printing of additional elements on top of braille dot has also been tested, and possible use for differentiation of the written notation is shown. This paper also indicates the importance of technological and operating conditions in UV inkjet braille printing. It predicts a significant role of UV inkjet in braille printing. Originality/value This paper provides a detailed review of UV ink-jet printed braille: possibilities, advantages and application.

Considering that optical properties play a very important role in the printing industry, this research focused on analysing the optical properties (opacity, whiteness, brightness and yellowness) of laboratory made papers from recycled wood pulp, with the addition of different straw contents, coated with titanium dioxide white ink. Titanium dioxide white ink was applied on laboratory papers to achieve optical characteristics as those of commercial papers recommended by ISO 12647. All the coated laboratory papers presented whiteness within the recommendations of the standard. Almost all the coated papers made with the addition of straw pulp achieved satisfactory optical properties, especially those containing 10% and 20% straw pulp. Coated laboratory papers containing 10% and 20% wheat pulp were comparable to commercial paper and reached a similar value of brightness, while their opacity and yellowness values were even better than those of commercial paper. In order to preserve the natural appearance of papers made with the addition of straw pulp, it is possible to conduct selective white printing as background for high-quality printing.

In order to achieve high-quality colour prints by using an electrophotography (EP) printing machine, it is necessary to prepare the printing substrate. Additional treatment may be needed to achieve better substrate surface tension for optimally attaching the liquid EP ink to the paper. To ensure good adhesion of the ink to the printing substrate, a corona treatment may be used. During the corona treatment, the surface of the paper is modified, and the ability of paper to accept the ink is improved. In this study, we will determine the possibility of realizing CMY prints and of achieving an increased range of tone value in EP digital printing. Based on the results, the new possible values of reproduced CMY tones will be determined, so that higher print quality can be achieved. The results show that the best colour reproduction is achieved without the use of corona power (0 W). The additional activation of 450 W corona will result in the greatest colour variation of ∆EC = 0.60, ∆EM = 0.60 and ∆EY = 0.48.

For high-quality black & white printing realized with an electrophotography printing machine, it is necessary to prepare the printing substrate. For optimal adhesion of the black liquid electrophotography ink to the printing substrate, it is necessary to apply additional treatment to meet ideal substrate surface tension by means of corona treatment and/or coating with fluid for regulating the surface tension (primer). This paper examines the influence of the corona power and the thickness of used fluid for the regulation of surface tension on the achromatic digital reproduction quality. Within the electrophotography printing process, this implies determining the differences in the colour gamut volume, the structure of characteristic screening elements, the amplitude-modulated screening, and the increase in the number of colour separations. The results show that the optimal colour tone values, colour gamut, and dot gain, high quality of digital prints will be realized without the use of the fluid for the regulation of surface tension and without activation of the corona power. That confirms that the FOGRA values for industrial standards can be used for quality electrophotography printing.

Objectives: To examine the effect of two aging protocols on the chemical and phase composition as well as the surface state of monolithic translucent zirconia ceramics. Material and Methods: Translucent zirconia ceramics KATANA-Zirconia STML with different surface treatments (no treatment, K1, K2; glazed, G1-G8; polished, P1-P8) underwent testing in order to examine how the two aging protocols (three-hour hydrothermal degradation in an autoclave at 134 °C and 2 bars: G1-G4, P1-P4, and sixteen-hour chemical degradation in four-percent acetic acid at 80 °C (ISO 6872): G5-G8, P5-P8) affect chemical composition, particularly the share of stabilizing yttrium oxide (Energy Dispersive XRay Fluorescence – EDXRF), phase composition (X-ray diffraction – XRD) and surface state in terms of roughness and gloss. Results: Aging protocols did not affect the tested chemical composition stability of specimens and a high share of stabilizing yttrium-oxide (≥10% of total content), which correlates with the absence of monoclinic phase. A decrease in gloss on all specimens is statistically significant. Chemical degradation substantially increased the surface roughness of tested specimens. Conclusions: Translucent monolithic zirconia demonstrated a stable chemical composition and resistance to tetragonal-to-monoclinic transformation. Surface gloss was significantly reduced, especially in polished specimens. Contrary to glazed specimens, the tested polished specimens manifested an increase in surface roughness. Glazing the surface of translucent monolithic zirconia produces better esthetic, tribological and hygienic effects than polishing.

Labels as a graphic product are important for information in declarations, especially for languages of smaller nations. Labels are increasingly required together with their ever more complicated technical performance, one of them being the desire to adapt the text to blind or partially sighted users. We therefore tested the possibility of using a declaration text in black with overprinted Braille cells with no or minor influence on legibility. The research was performed by analyzing the influence of printed cells on the achromatic halftone reproduction. The prints of the text and the overprinted Braille cells were made with a UV LED inkjet printer. Two different typefaces in two different sizes suitable for labelling were tested. The color properties were determined colorimetrically and the differences in the typographic tonal density of typefaces were measured with an image analysis. The legibility research was performed with the help of observers who read the plain printed text and the printed text in combination with overprinted Braille cells made with varnish. The results showed that an appropriate typeface and type size can reduce the influence of overprinted Braille on text legibility.

One of the problems in the offset printing technique is the picking of uncoated paper, which occurs due to the activity of pressure cylinder and sticky offset inks. To reduce offset ink stickiness, it is possible to add cheaper ink filler that will indirectly reduce the concentration of pigment. However, there is also a reduction in the colour tones and quality of reproduction. In this experiment we used: standard cyan offset ink (Sun Lit Express ink which consists of phthalocyanine based pigment) and high-quality gloss coated cardboard (250 g/m2 Euroart plus gloss). This paper aims to show how the CTP screening type (AM/FM mode) and the CTP line screening (80, 100, 120 line/cm and 10 μm, 20 μm 25 μm diameter of print elements) manifest on the reproduction quality of a standard gradation wedge. This research will create the possibility of correlating the factors of user reduction of pigment concentration and reproduction quality of cyan colour separation. By using the AM screenings and adding different concentrations of ink filler, more stable cyan prints are achieved.

Nowadays, Inkjet technology has become one of the most widespread printing technologies in car industry (car wrapping = printing and wrapping the whole vehicle or a part of a vehicle in printed foil). Printed wrap foils are, after the wrapping process, exposed to the same conditions as a lacquered vehicle: intensive sunlight, high and low temperatures, rainfall, snow, ice, particles or bugs that the vehicle encounters while driving, etc. In this paper we tested different types of wrapping foils (Orajet, 3M Scotchcal and 3M Controltac) and solvent inkjet inks to investigate the influence of different types of wrap foils on the real reproduction of UV ink jet coloured imprints, as well as their stability fluctuations during ageing. The inkjet prints age faster under the influence of UV light (Xenon lamp in SolarBox) in a period of 240 hours. The results show that the 3M Scotchcal foil has the best CMYK stability.

An increasing requisite regarding the reproduction quality of electrophotographic printing machines demands improvement of new electrophotographic toner formulation, especially used pigments. The subject of this paper is a comparison of prints realised by depositing high chroma (HC) and standard emulsion aggregation (EA) toner on gloss fine art paper. HC toner has a different composition of the cyan and magenta tones compared with the corresponding standard EA toner tones and therefore behaves differently under real conditions. The patches used for this experiment were cyan and magenta tone prints with tone values (TVs) of 0, 20, 60 and 100%. Ultraviolet (UV) degradation was measured over time intervals of 0, 6, 12, 24, 48, 96, 144 and 240 h for all patches. Results (laboratory values) were calculated using colorimetric difference. Values were plotted as a function of time in tonal degradation graphs. A model was created using non‐ linear regression‐based modelling. The experiment demonstrates that magenta patches are more susceptible to degradation in comparison with cyan patches. With the increase in tonal value, it is noticeable that the colorimetric difference is higher. Colorimetric differences calculated using HC magenta toner and standard EA cyan toner (100% TV) were higher than ΔE = 5, starting to appear after 6 h of exposure to UV radiance. After 12 h of exposure, colorimetric differences of standard magenta tones that were greater than ΔE = 5 alsonstarted to appear. Cyan patches (100% TV) printed with HC toner were more stable than the other patches, and after 240 h of exposure had not crossed the boundary of ΔE = 5.

The results from an investigation of the colour characteristic and changes in the size and shape of yellow screen elements of LEP (Liquid Electro-photography Printing) prints exposed to moist-heat ageing are presented. Three sample series are analysed: prints on the non-aged paper, accelerated aged prints and prints on accelerated aged paper. The results showed that prints on the aged recycled paper and on aged fine art paper show greater colour change than aged prints on non-aged paper. The tonal values were influenced by such printing substrates on the yellow reproduction. A decrease in colour differences of prints appears on the aged offset paper used as printing substrate by increasing the screen value in area of 10%-20%. Moist-heat aged prints on offset paper influences the decrease of yellow screen elements, which is not the case for the prints made on recycled paper and those made on fine art paper. Printing on the aged paper results especially in a 30% increased reproduction of the screen elements in darker tones. On all the three paper kinds greater deviations were found along the horizontal length of the screen element in comparison to the vertical diameter length.

The machine printing and rapid cultural development in Europe begins with the discovery of metal lettering at the end of the 15th century. This printing technique has been named the letterpress printing and is one of the greatest inventions of mankind. The development of printing was one of the main indicators of the development of individual countries. We believe that today in the world and in Europe the Croatian development of that age is significantly neglected. This paper presents European development and development in Croatia. This paper will contribute to a more accurate evaluation of Croatian printing and cultural level of that time by displaying Croatian achievements of that era, the printing staff, printed works and printing houses, throughout European and Croatian development of printing.

Trajnost crno-bijelih Inkjet otisaka izrazito je važna. Na žalost izlaganjem otisaka vlazi ima za posljedicu gubitak otisnutog sadržaja. Zbog nepostojanja univerzalne Inkjet boje potrebno je ispitati 3 tipične Inkjet boje: Inkjet otisci otisnuti crnom UV sušećom bojom, otisci otisnuti crnim dye Inkjet bojilima i otisci otisnuti crnim pigmentiranim Inkjet bojom. Za ovo ispitivanje napravljen je poseban uređaj koji će provesti simulaciju vlaženja (efekat oborinskih padalina) principom kap na kap. Eksperimentom su uključena 4 vremenska perioda vlaženja (0h, 1h, 6h i 24h). Za detekciju promjena akromatskih tonova primjenjena je kolorimetrijska metoda na temelju koje su izračunate kolorne devijacie CIE LAB ΔE00., The sustainability of monochrome Inkjet prints is extremely important. Unfortunately, exposure of the prints to moisture results in loss of printed content. Since there is no universal Inkjet color, it is necessary to examine the following 3 typical inkjet colors: Inkjet prints printed in black UV-drying color, prints printed with black dye Inkjet colorants and prints printed with black pigmented inkjet colourant. To do this test a special device was manufactured to simulate wetting principle of drop in drop (rainfall effect). The experiment included 4 periods of wetting (0h, 1h, 6h and 24h). To detect changes of achromatic tones the colorimetric method based on calculation colour deviation was applied (CIE LAB ΔE00).

High surface texture of textile materials appears rougher and more porous than other printing substrates which can cause excessive ink penetration. Also, high temperature thermal loads affect the characteristics of printed ink and cause structural changes of the textile substrate material as well. The aim of this paper is to determine the influence of thermal load on the print quality of cotton based fabrics with different knitting types via surface macro nonuniformity and line quality determination of the printed samples. The research results indicated that the thermal load had a negative influence on the line quality parameter and a positive effect on the macro non-uniformity parameter.

Svrha: Analizirati parametar translucencije (TP vrijednosti) staklokeramika izrađenih različitim tehnološkim postupcima te ispitati kako na TP vrijednosti utječu korozivna sredstva. Materijali i metode: Izrađena su po tri uzorka IPS e.max keramike (Ivoclar Vivadent, Schaan, Lihtenštajn) u trima bojama (A2, C2 i B3) s trima različitim tehnologijama izrade (slojevanje – e.max Ceram Dentin; toplo-tlačna tehnika – e.max Press; strojno – e.max CAD). Uzorci su bili u obliku pločica dimenzija 10 mm x 12 mm x 0,8 mm. Spektrofotometrom (X-Rite DTP 20 Pulse, Neu Isenburg, Njemačka) izmjerene su CIE L*a*b* vrijednosti za izračun parametra tanslucencije (TP vrijednost) prije i poslije izlaganja 4-postotnoj octenoj kiselini na 80 °C tijekom 16 sati (ISO 6872). Statistički podatci obrađeni su programom IBM SPSS 22. Rezultati: Značajno najmanje TP vrijednosti imao je IPS e.max Ceram Dentin, a najveće IPS e.max Press u svim bojama, prije i poslije izlaganja kiselini (p, The purpose of the study was to analyse translucency parameter (TP values) of glass-ceramics fabricated by different techniques and investigate the effect of the corrosive medium on TP values. Materials and methods: Three specimens of each type of IPS e.max ceramics (Ivoclar Vivadent, Schaan, Liechtenstein) were made in three colours (A2, C2 and B3) by three fabrication techniques (layering – e.max Ceram Dentin; heat-pressing – e.max Press; CAD/CAM – e.max CAD). Specimens were made in the form of plates (10 mm x 12 mm x 0.8 mm). CIE L*a*b* values were measured by a spectrophotometer (X-Rite DTP 20 Pulse, Neu Isenburg, Germany) before and after exposure to 4% acetic acid at 80 °C for 16 hours (ISO 6872) to calculate translucency parameter (TP values). Statistical data were analysed using the IBM SPSS 22 software. Results: IPS e.max Ceram Dentin had significantly the lowest TP values, and IPS e.max Press the highest TP values of all colours (A2, C2, B3), both prior and after exposure to acid (p

Printed fabric is widely used, and it is exposed to various influences. One unavoidable impact is heat treatment during subsequent maintenance – ironing. Hence, many printed textile materials are exposed to different temperatures. Textile can be printed with conventional (screen) and digital (Inkjet) print technologies. In this paper, we analyzed screen printed textile and its sustainability after heat treatment. Heat can not only change the reproduced colour, but also affects the print uniformity (print mottle). The goal of this paper was to find what could be controlled and changed in order to get long-lasting printed textile. We used one natural textile material – cotton that was printed with screen print technology. Constant parameter during the experiment was a time of heat treatment. Ironing temperature and screen mesh count were varied. Results showed that samples printed with smaller screen mesh count maintain print uniformity after heat treatment.