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The degradation characteristics of aniline and antimony in printing and dyeing wastewater during the micro-oxygenated hydrolytic acidification process and its effect on COD and ammonia nitrogen removal were investigated in this experiment. Firstly, the effects of control factors such as pH, dissolved oxygen (DO), and sludge concentration on COD and ammonia nitrogen removal in the hydrolysis acidification section were optimized. It was recommended that the pH value should be maintained at 6.5; low DO (0–0.5 mg/L) could assist in the conversion of nitrogen for subsequent treatment; the optimum treatment temperature was 25 °C; finally, it was recommended that the sludge concentration should be controlled at 4 mg/L during the operation. Secondly, the effects of aniline and antimony on COD and nitrogen removal were investigated. It was found that when the concentration of aniline was increased from 0.4 mg/L to 5.4 mg/L, the COD concentration in the effluent increased by 96.5%, which indicated that aniline was toxic to anaerobic sludge and obviously inhibited the degradation of COD. When the concentration of antimony was increased from 0.05 mg/L to 2.05 mg/L, the COD removal rate was only 2.9%, which was much lower than that of the water samples with no antimony added. The anaerobic sludge concentration decreased from 5.58 g/L to 3.44 g/L, which indicated that aniline and antimony had a strong inhibitory effect on the activity of anaerobic bacteria and inversely affected COD removal. [ABSTRACT FROM AUTHOR]

Flexographic printing is widely used in the packaging field, but there are still some problems in the printing of flexographic ink on non-absorbent substrates, such as low precision and unstable quality. In this paper, the printing process of flexographic ink is simulated. The interaction of fluid flow, temperature change, and solid deformation in flexographic printing is studied systematically by using the method of fluid–solid thermal coupling for the first time. The process of ink channel formation under static extrusion and fluid–solid thermal coupling was analyzed. The influences of printing pressure, printing speed, ink layer thickness, and ink viscosity on the ink channel were explored. The results show that the printing speed increases and the temperature in the stamping area increases. The printing speed is nonlinear related to the ink flow channel, the influence on the channel is slow at a low speed, the channel increases sharply at a medium and high speed, and tends to be stable at a high speed. When the printing speed is 200 m/min, the ink temperature in the stamping area is 1.5 °C higher than that at the entrance. With an increase in printing pressure, the ink flow channel width showed a trend of decreasing first and then stabilizing, and the pressure was about 0.4 MPa, showing a small fluctuation; the greater the pressure, the higher the temperature of the ink, which will change the performance of the ink and plate, causing adverse effects on the printing belt. The channel width showed obvious nonlinear characteristics with an increase and decrease in ink thickness. When the ink thickness is 30 μm, the deformation of the plate reaches the maximum, and the width of the ink circulation channel is correspondingly the widest. The change in ink viscosity has little influence on the stability of the ink's internal flow rate and temperature field. The research results provide theoretical support for the transfer of ink printing from gravure to flexo printing. [ABSTRACT FROM AUTHOR]

This work provides a method for the development of conductive water-based printing inks for gravure, flexography and screen-printing incorporating commercial resins that are already used in the printing industry. The development of the respective conductive materials/pigments is based on the simultaneous (in one step) reduction of silver salts and graphene oxide in the presence of 2,5-diaminobenzenesulfonic acid that is used for the first time as the common in-situ reducing agent for these two reactions. The presence of aminophenylsulfonic derivatives is essential for the reduction procedure and in parallel leads to the enrichment of the graphene surface with aminophenylsulfonic groups that provide a high hydrophilicity to the final materials/pigments. [ABSTRACT FROM AUTHOR]

The presented article shows the results of the analysis of the factors influence on the flexographic printing process with solvent based inks. The main factors influencing the printing process quality are identified, a semantic network of influence and dependencies of these factors is constructed. The priority of factors, taking into account their influences and dependencies, is established by the ranking method. Using the Pareto rule and the construction of the corresponding diagram, four main factors are identified, the influence of which provides 70 % of the studied process quality. It is established that the most priority factors are the parameters of the printing plate, the rheological parameters of the ink, the lineature of the anilox roller and the surface properties of the material to be printed, with the following calculated values: 150, 120, 105 and 90 units, respectively. The selected factors are used to analyse their impact on the flexographic printing process by means of fuzzy logic. Accordingly, a universal set, corresponding terms and a fuzzy knowledge base with the condition "If-Then" are established for these factors in the form of linguistic variables. The formed knowledge base is tested with the help of the Fuzzy Logic Toolbox package of the Matlab technological computing environment and the corresponding prognostic models of the influence of the selected factors on the printing process quality are constructed.

Solution processing of metal halide perovskites offers the potential for efficient, high‐speed roll‐based manufacturing of emerging optoelectronic devices such as lightweight photovoltaics and light emitting diodes at lower cost than achievable with incumbent technologies (e.g., Silicon). However, current perovskite fabrication methods are limited in their speed, uniformity, and patterning resolution, relying on subtractive postdeposition scribing for integration of modules and device arrays. Here, a method for flexographic printing of MA0.6FA0.4PbI3 at 60 m min−1, the fastest reported perovskite absorber deposition and the first report of inline drying integrated with roll‐based printing, is presented. This process delivers high‐resolution patterning (< 3 µm line edge roughness) and precise thickness control through rheological design of precursor inks, allowing scalably printed 50 µm features over large areas (140 cm2), while obviating damaging scribing steps. 2D scanning photoluminescence (PL) is applied to resolve correlations between ink leveling dynamics and optoelectronic quality. Integrating these highly uniform printed perovskite absorbers into n‐i‐p planar perovskite solar cells, photovoltaic conversion efficiency up to 20.4% (0.134 cm2), the highest performance yet reported for any roll‐printed perovskite cells is achieved. This study, thus, establishes flexography as a scalable approach to deposit precisely‐patterned high‐quality perovskites extensible to applications in emitter and detector arrays. [ABSTRACT FROM AUTHOR]

In the flexographic printing industry, anilox rolls play a pivotal role in determining ink usage. These rolls are characterized by anilox cells, which transfer ink to the final printed material. However, these rolls face wear and potential damage during their operational life, largely due to improper cleaning or debris accumulation in the ink duct. Such contamination compromises the ink capacity, impacting print quality. With the industry's need for consistent and high-quality prints, there is a growing emphasis on the development and consistent implementation of optimal anilox-roll operation methodologies. One cleaning method gaining traction is ultrasonic cleaning. This method employs ultrasonic waves in conjunction with a cleaning agent, providing a quick, efficient, and environmentally conscious cleaning alternative. Yet, there is limited scientific data on the actual condition of anilox rolls after ultrasonic cleaning. In this study, the surface of anilox rolls post-ultrasonic-cleaning was comprehensively examined using microscopic analysis. This assessment provided insights into the method's efficacy and potential for causing roll damage. The results showed that post-printing, rolls lost approximately 20% of their ink capacity, and ultrasonic cleaning effectively restored the ink capacity of the undamaged rolls. However, for rolls with pre-existing damage, the ultrasonic cleaning process exacerbated the damages, leading to complete delamination in some instances. This study underscores the potential of ultrasonic cleaning in restoring anilox-roll efficiency but also highlights the need for caution with damaged rolls. [ABSTRACT FROM AUTHOR]

The presented article shows the results of the analysis of the factors influence on the flexographic printing process with solvent based inks. The main factors influencing the printing process quality are identified, a semantic network of influence and dependencies of these factors is constructed. The priority of factors, taking into account their influences and dependencies, is established by the ranking method. Using the Pareto rule and the construction of the corresponding diagram, four main factors are identified, the influence of which provides 70 % of the studied process quality. It is established that the most priority factors are the parameters of the printing plate, the rheological parameters of the ink, the lineature of the anilox roller and the surface properties of the material to be printed, with the following calculated values: 150, 120, 105 and 90 units, respectively. The selected factors are used to analyse their impact on the flexographic printing process by means of fuzzy logic. Accordingly, a universal set, corresponding terms and a fuzzy knowledge base with the condition "If-Then" are established for these factors in the form of linguistic variables. The formed knowledge base is tested with the help of the Fuzzy Logic Toolbox package of the Matlab technological computing environment and the corresponding prognostic models of the influence of the selected factors on the printing process quality are constructed. [ABSTRACT FROM AUTHOR]

Ethylene is a type of gas that fruits and vegetables can produce naturally. The release of ethylene gas from fruits and vegetables causes them to ripen and undergo physical, chemical and biological changes, such as changes in the appearance in terms of shape and colour, changes in firmness and texture, changes in taste and changes in nutritional value. Furthermore, it also facilitates the growth of microorganisms. These changes lead to spoilage if the fruit or vegetables are left to over ripen. Therefore, the prevention and reduction of damage caused by the ripening of fruits and vegetables entail reducing or slowing down the release of ethylene gas produced by them. This research project aimed to study the properties of activated carbon and potassium permanganate (KMnO4) modified activated carbon, applied as a printing layer on plastic materials for bananas, in terms of their adsorption and decomposition of ethylene. Active and water‐based flexography printing inks were prepared from water‐based binder and ethylene adsorbing and scavenging agents (activated carbon and KMnO4 modified activated carbon) at various concentrations of active agents, that is, 0.0, 5.0, 7.5 and 10.0%w/v. Then, those inks were printed on polypropylene plastic substrate. The delayed ripening of fruits results showed that the plastic materials coated with modified activated carbon inks delayed the physiology disorder (colour and firmness changing about 250% and 226%) and prolonged the storage time up to 14 days when compared with control. In addition, the functional ink layer also presented a high efficiency of abrasion resistance of about 75 cycles of rubbing at 1.8 kg. The products that stem from this research can be applied as packaging for fruits and vegetables in the form of bags, stickers and product pads that can help extend the life and slow the ripening of fruits and vegetables. [ABSTRACT FROM AUTHOR]

With the extensive implementation of new technologies in printing and reprographic printing the manufacturing methods of mass printing products, including labels, tags, and packaging, which often become the objects of forensic document analysis, have changed dramatically. The article describes the modern methods of color printing and reprographic printing used in manufacturing of such products. The work also provides an overview of the most common modern methods and types of color industrial printing used in the production of labels, tags, and packaging. The author describes the diagnostic complexes of features of these methods displayed at the raster level in the resulting prints (images).

This work provides a method for the development of conductive water-based printing inks for gravure, flexography and screen-printing incorporating commercial resins that are already used in the printing industry. The development of the respective conductive materials/pigments is based on the simultaneous (in one step) reduction of silver salts and graphene oxide in the presence of 2,5-diaminobenzenesulfonic acid that is used for the first time as the common in-situ reducing agent for these two reactions. The presence of aminophenylsulfonic derivatives is essential for the reduction procedure and in parallel leads to the enrichment of the graphene surface with aminophenylsulfonic groups that provide a high hydrophilicity to the final materials/pigments.

Despite numerous methods to optimise their operation and parameters, anilox rolls are subject to rapid wear during use and due to improper cleaning processes. Therefore, regular diagnosis is needed. In this study, X-ray fluorescence (XRF) analysis based on Fe and Cr was used to determine the elemental compositions of raster cylinder coatings. Due to the layered composition of the anilox roll, where Cr2O3 coating is applied on the iron core, evaluation of the composition of the roll surface can be used to detection of anilox damage. A portable XRF apparatus was used to identify selected elements even at low concentrations of <1%. In this work, it was proved that XRF can be a preliminary, rapid method for assessing the technical condition of an anilox cylinder. The XRF technique can be safely used in non-destructive chemical analyses of the anilox rollers' condition in flexographic printing technology, and chemical information that aids in their use may be routinely obtained, thus enabling high-quality printing. This is a pioneering study in which the XRF spectroscopy technique was successfully used to anilox roll condition assessment. [ABSTRACT FROM AUTHOR]

To achieve high-performance printed electronic devices, scalable and cost-effective printing of high-quality metallic electrodes with narrow gaps, such as for transistors with short channel lengths, is desirable. Here, we demonstrate short channel (<10 μm) transistors, using thin (<100–200 nm) electrodes fabricated by flexographic printing with nanoporous stamps, with single-wall carbon nanotubes (SWCNTs) as the network semiconductor. The nanoporous stamps comprise polymer-coated vertically aligned carbon nanotubes and facilitate control of the printed ink thickness in the 50–200 nm range. The measured on–off ratio and mobility meet or exceed those of previously reported SWCNT network transistors fabricated by alternative printing methods. [ABSTRACT FROM AUTHOR]

Flexography prints on non-absorbent as well as absorbent substrates using liquid ink. With developments in photopolymer plate and anilox roll manufacturing technology, we can print half tone with screen frequencies exceeding 150 LPI (Lines per Inch) where the print quality can be comparable with offset printing results. This has helped flexographic printer to reproduce the blackand-white, single colour tone and full colour graphic original, satisfying the printing and packaging needs of many customers. But unlike other printing technologies in flexographic printing screen frequency of plate i.e. image carrier and engraving line frequency of anilox roll collectively affect the smoothness and uniformity of reproduced half tone image. Furthermore, the LPI of the screen used in plate making also adds to variation in tonal reproduction. In the presented work 3 line frequencies expressed in CPI (Cells per Inch) of anilox roll and 5 screen frequency of image carrier are selected and their effect on print characteristics is studied using the plot of theoretical dot area against apparent dot area. Given the sizable capital investment involved in manufacturing of anilox roll, this work is directed at finding the optimum combination of screen frequency and line frequency required to achieve tonal balance. [ABSTRACT FROM AUTHOR]

The security and protection of printed products against counterfeiting have become more advanced and increasingly used in the field of graphics technology. In this research, conventional process black (PB) and UV luminescent (UVL) inks used in flexography, modified by nanoscale silicon dioxide (SiO2), anatase and rutile titanium dioxide (TiO2), and zinc oxide (ZnO) at different concentrations were used. The purpose of adding nanoparticles to these inks was to protect PB and observed UVL inks from counterfeiting without significantly affecting the optical appearance and colourimetric properties of the printed motives. The results have shown that nanoparticles did not significantly affect the spectral reflectance of UVL inks observed under UV irradiation or the visual effect of UV luminescence. In addition, the nanoparticles had a negligible effect on the optical and colourimetric properties of PB inks, as evidenced by a slight increase in colour lightness after the addition of nanoparticles. Indirect detection of nanoparticles through their interaction with PB and UVL inks was possible through FTIR-ATR spectroscopy, which showed changes in the spectra of PB and UVL inks with nanoparticles compared to nanoparticle-free inks in the fingerprint region. This research opened the possibility of expanding the use of nanoparticles of different types and concentrations for process, spot, luminescent and other special and conventional inks in the field of graphic technology. [ABSTRACT FROM AUTHOR]

Flexographic printing plate is used for the transfer of image onto a printing substrate. The surface of printing plate is stretched lengthwise when the plate is mounted on plate cylinder. As a result, the print length on the impression is always longer than the actual length of the plate. Prepress must compensate for this difference in length. The result of wrong plate distortion is different print length in flexography compared to the processes that follow printing. The aim of this paper is to research the influence of repeat length in printing and polymer plate thickness on the factor distortion. The distortion factor values were calculated using the derived formulas. Regardless of the repeat length in printing, the value of the thickness factor for a particular printing plate is constant. However, the values of the distortion factor decrease with the increasing thickness of the polymer plate and the decreasing of the total plate cylinder circumference.