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This study aims to identify the results of social and environmental sustainability strategies in flexographic printing processes of labels and labels. The research consisted of a literature review, followed by an exploratory-descriptive study of qualitative nature. Data collection took place in a primary way through a semi-structured on-site interview with the company's owner, and also involved access to documents. In conclusion, the article analyzes the results of two years in relation to social and environmental practices and the identification of sustainability practices obtained in the company.

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.

Flexographic technology usage is increasing in recent years. Predicted growth in the technology usage intensifies the demand for improved quality. It is expected that flexographic printing will achieve greater results than ever before. Since this technique is used in the printing of shrink sleeve packaging, it is imperative to meet the technical and economic requirements of the shrink sleeve product. This is primarily to ensure gliding of the white printing material. The amount of white should be as small as possible, making the sliding of the material optimal and the quality of the print better. Therefore, the quality of the printing was measured by changing the conditions of slippage and white color. This research has established a correlation between the thickness of the white layer and the reduction of print quality over thin lines.

The FMCG sector (Fast Moving Consumer Goods) is one of the largest industries in the world wherein the brands are reliant on the customer attraction and product sales worldwide. It is important for brands to maintain the quality and color consistency of these products. FMCG labels printed with Spot colors by Flexography process is not cost-effective due to higher job changeover times and wastage. The most effective way of ensuring spot color reproduction is implementing Expanded Color Gamut (ECG) printing by using a fixed set of colors with four process colors namely Cyan, Magenta, Yellow, Black (CMYK) along with three colors Orange, Green and Violet (OGV). These seven colors provide eye-catching graphics and a larger gamut so as to reproduce maximum number of Pantone® colors. The evaluation of spot color reproduction was carried on a Nilpeter FB-430 Narrow Web Flexo press that included runs viz. Initial, Optimization, Fingerprinting, Characterization and Validation on Polypropylene substrate with UV based inks. The runs were carried as per Idealliance® specifications. The aims and tolerance as per ISO 12647-2 with CRPC 6 GRACoL 2013 for CMYK while ISO 20654 Spot Color Tonal Value (SCTV), Chroma and Hue for OGV were achieved. The customized Characterization Test Chart with 2016 patches for CMYKOGV for profile generation and Verification Test Chart with 799 patches of Pantone® Solid Coated from the Digital Library was created in CGS Oris XGamut. These Test Charts were measured using X-Rite EyeOne iO automated device. The magnitude of color match for Spot Colors by expanded gamut printing was verified on a narrow web flexography press. The gamut analysis between CRPC 6 and CMYKOGV showed that from the geometric region of Pantone® Colors Inside CMYKOGV Gamut and Outside CRPC6 Gamut, 85% of the Pantone colors were reproduced below Delta E 2.5.

With the development of flexible electronics, researchers have endeavored to improve the characteristics of the commonly used indium tin oxide such as brittleness, poor mechanical or chemical stability, and scarcity. Currently, many alternative materials have been considered such as conductive polymers, graphene, carbon nanotubes, metallic nanoparticles (NPs), nanowires (NWs), or nanofibers. Among them, silver (Ag) mesh/grid NPs or NWs have been considered as an excellent substitute due to the good transmittance, excellent electrical conductivity, outstanding mechanical robustness, and cost competitiveness. So far, much effort has been devoted to the fabrication of Ag mesh/grid, and many methods such as printing technology, self-assembly, electrospun, hot-pressing, and atomic layer deposition have been reported. Here printing technologies include jet printing, gravure printing, screen printing, nanoimprint lithography, microcontact printing, and flexographic printing. The solution-based self-assembly usually combines with coating, template, or mask assistance. This review summarizes the characteristics of these fabrication methods for the Ag mesh/grid with its related applications in electronics. Then the prospect and challenges of the fabrication methods are discussed, and the new preparation approaches and applications of the Ag mesh/grid are highlighted, which will be of significance for the applications in electronics such as transparent conducting electrodes, organic light-emitting diode, energy harvester, strain sensor, cells, etc.

A green approach for the functionalization of multiwalled carbon nanotubes (MWNTs) with hydrophilic groups and their use for the development of an ecofriendly conductive ink are described here. A known organic functionalization of MWNTs, 1,3 dipolar cycloaddition of catechol substituted azomethine ylide, is performed here for the first time, in the solid phase. The functionalized MWNTs were then mixed with graphene nanosheets in ethanol to produce a hydrophilic and highly conductive all-carbon hybrid. The end product was finally mixed with resin to produce a water based conductive ink. In the total procedure, a solid state reaction and non-toxic and eco-friendly solvents like water or alcohols have been used to produce a totally green conductive ink for industrial printing techniques like flexography or gravure printing.

Even though textile labels are not often the subject of research, their quality must not be neglected. Printed typographic elements (i.e. letters and texts) must be visible regardless of textile ribbons and typeface or type size to be printed. Thus, the aim of the research was to qualitatively and quantitatively analyze and evaluate the text printed with flexography in two different typefaces (Helvetica and Verdana) in three different type sizes (4, 6 and 8 point) on five textile ribbons made of polyester and polyester/cotton mixture in two different weaves (plain and satin). The results of our research showed that the quality of printed letters is influenced by the properties of textile ribbons as well as by the chosen typographic features. When textile ribbons were composed of polyester filaments, the quality of prints was better than in the case of the mixed composition with cotton fibers. The coating and previously dyed textile ribbons had a positive influence on the quality of printed letters. The typeface Verdana gave more distinct and contrasted printed letters than Helvetica. The quality of printed letters (measured by the cover factor) decreased with the reduced type size; letters (and text) in a smaller type size (4 point) were hence, depending on the properties of textile ribbons, less visible.

Встановлено, що одним з найбільш важливих показників інтегральної обкладинки з широкими клапанами є контурна стабільність, яка характеризується відхиленням зовнішніх контурів від прямокутної побудови. Цей параметр формується під час проходження заготовки обкладинки через механізм координувально-транспортувального блоку лінії для виготовлення інтегральних обкладинок. Зазначений показник залежить як від витратних матеріалів (папір, картон-хромерзац, клей, термоклей), так і від тиражу, а також від геометричних і фізико-механічних параметрів деталей координувально-транспортувального блоку, які контактують з обкладинкою. Розроблено узагальнену логічну схему в параметричному вигляді моделювання процесів технологічного забезпечення контурної стабільності обкладинок та якості й експлуатаційних властивостей деталей координувально-транспортувального блоку лінії для виготовлення інтегральних обкладинок з широкими клапанами. Така схема дозволяє встановити взаємозв’язок між режимами комплексної технології оздоблювально-зміцнювальної обробки, геометричними і фізико-механічними параметрами поверхні циліндричних деталей координувально-транспортувального блоку лінії для виготовлення інтегральних обкладинок з широкими клапанами, визначити їх вплив на експлуатаційні характеристики поліграфічного обладнання та якість готової продукції. Підвищення показників якості обкладинок характеризується істотним зменшенням відсотку їх відбракування залежно від накладу після застосування комплексного технологічного процесу оздоблювально-зміцнювальної обробки. Застосування узагальненої логічної схеми моделювання процесів технологічного забезпечення контурної стабільності обкладинок та експлуатаційних властивостей циліндричних деталей координувально-транспортувального блоку лінії для виготовлення інтегральних обкладинок з широкими клапанами є доцільним при комплексній обробці як деталей лінії з виготовлення обкладинок, так для циліндричних рухомих деталей іншого поліграфічного обладнання (машин для флексографічного друку та ін.).

Flexographic printing, which involves high-speed contact of an inked stamp against a substrate, is of increasing interest for scalable manufacturing of electronics in new formats. However, the adaptation of flexography to thinner, finer features which are generally required for printed electronics requires improved understanding of stamp-substrate contact mechanics. Here, we present a desktop plate-to-roll (P2R) printing apparatus which enables the study of flexographic printing in a semi-continuous format that mimics industrial printing. In particular, we tailor the specifications of the machine to use nanoporous stamps which have been shown to enable flexographic printing of ultrathin ink features with micron-scale linewidth. Printing with nanoporous stamps requires precise control of stamp-substrate contact force (2–250 mN) and elimination of shear force at the interface among others; these are accomplished using a flexure-supported substrate, and by coordinated rotary-linear motion of the system. We detail the design and evaluation of the P2R machine and demonstrate printing of high-resolution features (

Many government documents can be forged, even documents which are marked with "Eagle Stamp" sometimes unfortunately fake. Who is in his hands this "Eagle Stamp" sees that is enough to prevent counterfeiting and fraud completely. But what happens in reality is quite the opposite. "Eagle Stamp" is usually printed on formalized paper documents by using a relief printing plates. Such as letterpress and flexographic printing, When we need to use flexographic printing technology to print a new design structure of the "Eagle Stamp"-which build from lines and dashes in order to prevent its reproduction and therefore preventing government documents counterfeiting, we have to be careful, so the research investigated into critical parameters such as flexographic plate thickness, flexographic plate shore, line or dash thickness and the spaces between lines or dashes, digital file resolution, relief depth … etc., that help to comprehend the effect of these and other parameters on the final printed "Eagle Stamp" and to determine which of these parameters can produce a perfect ink film module to print high quality and valid "Eagle Stamp" that can be used on formalized paper documents without possibility for reproduction or counterfeiting. So our pre-press work prior to printing is designed to serve the research hypothesis, that choosing the appropriate parameters will make any attempted reproduction of our design very difficult to replicate After experimental work study, the results have shown that using photopolymer flexographic plates with compatible parameters and printing the samples with appropriate printing machine, would result in very successful and clear printed eagle stamps build in prepress stage from lines and dashes in order to achieve the research objective

Hypothesis Selective ozone treatment of Polydimethylsiloxane (PDMS) print-stamps may facilitate local de-wetting of Krytox®1506 oil; the resulting printed pattern can be used as a masking liquid during roll-to-roll vacuum-metallization, exemplified with Ag. This novel method may exploit high-throughput manufacture without chemical etchants or elevated temperatures for thin-film electronics. Experiments The mechanism for selective wetting arose from O3 treatment of PDMS through a shadow-mask to vary surface-energy due to formation of polar silanol (Si-OH) replacing surface methyl groups leading to contact angle reduction from 40°-9° for oil on PDMS. Oiled PDMS was (1) metalized itself and (2) used as a stamp to print onto polyethylene-terephthalate, consisting of oil pick-up/de-wetting/transfer-to-substrate/metallization. Findings Ag (520-568 nm) thick was deposited outside oiled regions, surpassing ∼20 μm resolution of commercial printing. On metalized PDMS, minimum line widths were 2.6 μm (with 10 μm edge-grading from centrifugal oil spreading) or widths of 24 μm (no Ag grading) following spin-coating/roll-coating oil respectively. The progressive effect of thinning oil via five successive stamp-to-substrate impressions, produced line widths of 14 μm (with graded edge of 7.6 μm via spreading from stamp-substrate compression). Developments may reduce reliance on laser engraving/photocuring, and could enhance micro-contact printing through liquid dynamics vs. topographical relief structures.

This research analyzed the printability of compostable films commercialized in the Thai market such as PLA/PBAT and PBAT/starch; and to comply with EN 13432 standard by using flexographic water based ink. A narrow web flexographic printing press was set up and opperated. Print quality parameters such as optical density, tone reproduction, print contrast and print uniformity were investigated. Results showed that these compostable films were hydrophobic in nature, in combination with fracture and voids of substrates’ surface. Even the substrates could be printed relatively well but showed poor ink adhesion. Surface treatment, therefore, was necessary, but having limitation. Anilox line screen 700 lpi and printing speed at 30 m/min were preferable to achieve the optimum tone reproduction and print contrast. This was based on the image resolution of 133 lpi and corona dosage at 500 watt-min/m2. Images of printed samples from SEM and SPM indicated that the fracture surface and void of films could lead to decrease their printability. It was found that starch blend gave better results as being a filler of the surface roughness of the substrate..

The intensive use of flexographic printing for packaging decoration and the increased consumer demands for it require an in-depth study of the factors that influence the prints’ quality. In this paper, we examined the test prints obtained at a flexographic proofer. Images on cardboard were printed by the environmentally friendly inks made by a Ukrainian manufacturer. The effect of the cardboard surface layer on the microgeometry of the prints created by cyan, yellow, black, and magenta inks has been shown. It has been established that the roughness parameter Ra for a two-layer coated cardboard is reduced by 3times as compared to the uncoated cardboard. The photographs of the microstructure of the prints’ surface, their profile demonstrate a significant effect of the chalked coating on the image quality. It has been confirmed that the ink layer smooths out the micro-roughness of the print surface. However, when printed on the uncoated cardboard, the ink particles penetrate deeper into the structure and do not completely smooth out its micro-roughness. If the size of the printing element is smaller than the size of the cell on a raster roller, it falls into this cell and the ink is applied beyond the boundaries of the image. As a result, a spot of an arbitrary shape is formed on the print instead of a raster dot of a certain size, that is, the so-called "inverse tone transfer" occurs. We have measured the densitometric indicators of prints (optical density, gray balance), which significantly affect the quality of the product. Based on a Harrington's desirability function, the maximum permissible values of optical density, evenness of printing, contrast, dot gain of raster elements, and trapping, have been calculated. According to the generalized optimization criterion, a comprehensive index of the prints’ quality has been determined, which could ensure the predicted quality of a would-be run of the printed products, and would make it possible to adjust the printing process if necessary

As a key component of satellite flexographic printing equipment, the vibration characteristics of the central impression cylinder have an important effect on the product quality. In order to improve dynamic characteristic of the central impression cylinder, the modal analysis on the central impression cylinder is carried out in combination with finite element software in this paper. Then, the modal properties are systematically compared between the central impression cylinder with circulating cooling water and without. The results show that the natural frequency of the central impression cylinder is greatly reduced based on the fluid–solid coupling method. Simultaneously, the natural frequencies and mode shapes of the central impression cylinder based on the finite element analysis are verified by an experimental test. The simulation results are in good agreement with the experimental results, indicating the effectiveness of the finite element model and experimental method used in this study.

Recent technological advancement in flexographic printing has allowed flexography to catch up with other R2R processes such as gravure printing in the printed electronics field. However, there are many process parameters involved in flexography that can affect the print quality. This work attempted to achieve finer line printing compared to the current 45–100 µm printed line width range of flexography by manipulating and studying these process parameters. A design of experiments was conducted to investigate the influence and interaction of various process parameters such as anilox volume, anilox force and printing force on the printed line width. After identifying the key process parameter from the design of experiments, another in-depth study of the key process parameter was conducted to further investigate how printed line width was affected. The results showed that the printing plate was elastically deformed with a range of 50–400 N printing forces. Beyond the 400-N printing force, the printing plate experienced plastic deformation.

Naresuan University Journal: Science and Technology, 30, 4, 104-118

Printing of optical waveguides is an approach to large-volume implementation of optical data transmission in conventional electronic systems. Flexographic printing can be used to apply optical waveguides with circular-segment cross-sections to planar substrates. In this work, a concept for integrating printed optical waveguides into printed circuit boards (PCBs) is investigated, taking the requirements of industrial processing into account. A planar waveguide structure model is defined that is applicable to lamination processes used in PCB manufacturing. Due to thermal stress on the substrate during this process, polymer waveguides are printed on polyimide (PI) substrate. To ensure optical functionality, matching refractive indices in the form of printed cladding structures are required. Manufacturing multilayer waveguide structures requires new processes for generating the end facets of the waveguide core. To reduce the attenuation caused by optical coupling, one primary requirement is low facet roughness. In this paper, we present a way to flexographic print fully cladded waveguides on PI substrates. Different waveguide layer compositions are characterized with respect to their geometry by confocal measurements. Milling with monocrystalline diamond cutters is presented as a method for preparing the end facets. Finally, the attenuation of the prepared waveguides is measured and discussed as a function of the waveguide and end facet properties. By this, flexographic printed and ready-to-integrate waveguides are achieved, approaching the target of optical PCBs.

Resistive random-access memory is a candidate for next-generation non-volatile memory architectures. In this study, we use flexographic roll-to-roll printing technology for deposition of the resistive layer, a printing method that allows fast and cost-effective fabrication to create non-volatile resistive memory devices. Metal-free organic polymers blends composed of poly(methyl methacrylate) (PMMA) and a surplus of poly(vinyl alcohol) (PVA) serve as the active layer. Microscopic studies of the roll-to-roll printed layers show circular domains of PMMA embedded in PVA. The influence of the PMMA content in the polymer blend is investigated with respect to the performance and reliability of the resistive memory cells. Electrical characterization reveals a retention time of at least eleven days, a Roff/Ron ratio of approx. two orders and write/erase voltages of + 1/−2 V.

Functional model inks were formulated and printed using flexography in order to assess the influence of ink extensional elasticity and print velocity on the morphological and electrical properties of printed layers. Increased extensional elasticity and higher print velocity resulted in the printing of more isotropic prints, both morphologically and electronically. Furthermore, a correlation between the prints’ morphological and electrical anisotropy strongly suggests that print uniformity has a considerable influence on functionality and that ink rheology may be used to control such characteristics.

The emergence of solar cells on flexible and bendable substrates has made the printing process a ubiquitous tool for the fabrication of these devices. The various printing techniques available now such as inkjet, screen and flexography offer cost- effectiveness, user-friendliness and suitability for mass production. While downscaling the fill factor and efficiency of organic solar cells. A multilayered structure, the combination of different printing techniques avails the variety of thickness and resolution required for each layer in the production of an organic solar cell. In this review article, we discuss the suitability of the inkjet and screen printing processes to produce organic solar cells. We also discuss various challenges involved in the fabrication of organic solar cells using these two techniques and the possible solutions for the same. We also provide an analogy that both processes share. Further, we consider future possibilities of combining these printing technologies to produce organic solar cells to improve device performance.

Photopolymer flexographic printing plate is a new photopolymeric material used for microdevices fabrication. This work demonstrates that a photopolymer flexographic master mold can be used for the fabrication of PDMS (polydimethylsiloxane) microdevices by a multi-step manufacturing process. The methodology entails three main fabrication steps: (1) a photopolymer flexographic printing plate mold (FMold) is generated by UV exposure through a transparent film, (2) an epoxy resin mold (ERmold) is fabricated by transferring the features of the photopolymer mold and (3) a PDMS microdevice is manufactured from the epoxy resin mold. The characterization of the manufactured PDMS microdevices was performed using scanning electron microscopy (SEM) and profilometry. Results showed high accuracy in the replication of the profiles. To show the feasibility of the fabrication process a microdevice for microdroplet generation was designed, manufactured and tested. Hence, the manufacturing process described in this work provides an easy, robust, and low-cost strategy that facilitates the scaling-up of microfluidic devices without requiring any sophisticated equipment. Fil: Olmos Carreno, Carol Maritza. Universidad Tecnológica Nacional. Facultad Regional Haedo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Vaca Mora, Andrea Vanessa. Universidad Tecnológica Nacional. Facultad Regional Haedo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Rosero, Gustavo. Universidad Tecnológica Nacional. Facultad Regional Haedo; Argentina Fil: Peñaherrera Pazmiño, Ana Belén. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Tecnológica Nacional. Facultad Regional Haedo; Argentina Fil: Pérez Sosa, Camilo José. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Tecnológica Nacional. Facultad Regional Haedo; Argentina Fil: de Sá Carneiro, Igor. Universidad Tecnológica Nacional. Facultad Regional Haedo; Argentina Fil: Vizuete, Karla. Universidad de Las Fuerzas Armadas Espe; Ecuador Fil: Arroyo, Carlos R.. Universidad de Las Fuerzas Armadas; Ecuador Fil: Debut, Alexis. Universidad de Las Fuerzas Armadas; Ecuador Fil: Perez, Maximiliano Sebastian. Universidad Tecnológica Nacional. Facultad Regional Haedo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Ingeniería Biomédica; Argentina Fil: Cumbal, Luis. Universidad de Las Fuerzas Armadas; Ecuador Fil: Lerner, Betiana. Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Ingeniería Biomédica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Tecnológica Nacional. Facultad Regional Haedo; Argentina

Printed electronics, PE, is one of the fastest growing technologies in the world; it allows the construction of electronic devices in low-cost flexible substrates by printing techniques (e.g., screen, gravure, offset, flexography and inkjet printing) traditionally used in several industries (e.g., graphics arts, textiles, polymers). In PE, ink pigments are replaced by metallic particles or precursors that impart the electrical conductivity to the resultant printed patterns. This work reviews the available solid metal formulations used for conductive inks and pastes, focusing on both metallic particles and polymeric components. The influence and technical requirements of most commonly used printing techniques, along with the post-processing treatments to reach the aim performance in the resultant inks has been addressed. Considering that PE is an emerging profitable field with novel applications in radio frequency identification (RFID) tags, thin-film transistors (TFT), light-emitting diodes (LED), transparent conductive electrodes (TCE) and organic solar cells (OSC), among others, it is crucial to know how printed formulations work and how they can be molded to fulfill the applications requirements. In this review, apart from metallic solid particles that has been widely reviewed in the past, the chemistry of polymer matrices has been focused in order to elucidate its important role in resultant inks performance. Novel outstanding formulations, such as reactive or metal-organic-decomposition (MOD) inks, have been presented., The authors gratefully acknowledge the financial support of the NORTE 2020 project TSSIPRO (Technologies for Sustainable and Smart Innovative Products, NORTE-01-0145-FEDER-000015) and the COMPETE project iFACTORY: Novas Capacidades de Industrializac¸ ão (POCI-01-0247-FEDER-002814).

Printing of ultrathin layers of polymeric and colloidal inks is critical for the manufacturing of electronics on nonconventional substrates such as paper and polymer films. Recently, we found that nanoporous stamps overcome key limitations of traditional polymer stamps in flexographic printing, namely, enabling the printing of ultrathin nanoparticle films with micron-scale lateral precision. Here, we study the dynamics of liquid transfer between nanoporous stamps and solid substrates. The stamps comprise forests of polymer-coated carbon nanotubes, and the surface mechanics and wettability of the stamps are engineered to imbibe colloidal inks and transfer the ink upon contact with the target substrate. By high-speed imaging during printing, we observe the dynamics of liquid spreading, which is mediated by progressing contact between the nanostructured stamp surface and by the substrate and imbibition within the stamp-substrate gap. From the final contact area, the volume of ink transfer is mediated by rupture of a capillary bridge; and, after rupture, liquid spreads to fill the area defined by a precursor film matching the stamp geometry with high precision. Via modeling of the liquid dynamics, and comparison with data, we elucidate the scale- and rate-limiting aspects of the process. Specifically, we find that the printed ink volume and resulting layer thickness are independent of contact pressure; and that printed layer thickness decreases with retraction speed. Under these conditions, nanoparticle films with controlled thickness in the

Flexographic printing technology is an economical, productive, low maintenance and versatile technology. However, the removal of these inks by the traditional flotation process during paper recycling is not possible since they remain dissolved in the waters, making necessary the development of alternative methods. Recent studies have revealed the potential use of nanocellulose (NC) combined with a cationic polyacrylamide to remove flexographic inks from wastewater. The use of a natural polymer, such as chitosan, would be an important improvement of this treatment because NC and chitosan are the two most abundant natural polymers with interesting properties, such as non-toxicity and biodegradability. Therefore, in this study the decolorization of three flexographic inks (copper phthalocyanine blue, carbon black and diarylide yellow) by the sequential addition of cellulose nanofibers, produced from recycled paper, and chitosan has been evaluated. Results show that this eco-friendly approach has high potential for the removal of water-based inks with an almost 100% reduction of turbidity and ink from the wastewater. Moreover, the final sludge containing nanocellulose and inks could be used to reinforce the pulp of the middle layers of carton board, improving the mechanical properties of the product and reducing waste generation.

Application of gas chromatography allows obtaining basic data on the mixture composition, that is revealing the main component, discovering availability of impurities of macro- and microcomponents at qualitative and quantitative levels. It is possible to obtain data on the presence of moisture using IR spectroscopy. Quantitative parameters on the presence of water can be obtained using titration methods аccording to K. Fisher or using gas chromatography with a thermal conductivity detector. Density parameters and fraction composition allows revealing (indirectly) the presence of other impurities, as well as establish conformity of the object under research to requirements of the relevant normative and technical documentation. The obtained complex is sufficient for the formation of conclusions in categorical form and does not require additional data provided that the following signs are met, which include: 1. Presence of ethyl alcohol as the main component (usually more than 90 %). 2. Dehydration is one of the key indicators that allows the use of solvent for flexography. 3. Presence of components added to ethanol to provide the required volatility (eg, esters). 4. Low content of heavy (high boiling) components. The paper considers differences of solvents for flexography from other similar objects that can be important for expert research. Besides differences in the composition and properties of considered products, also the differences in the characteristics of the goods in the Ukrainian classification of goods of foreign economic activity are demonstrated. An example of use of data obtained as a result of chemical research, by an commodity expert in formulating categorical conclusions on delivered question is offered.

The textbook deals with the theoretical and practical issues of flexographic printing technology. Much attention is paid to prepress and printing processes. Data on the adhesion of flexographic inks are presented, and theoretical and practical issues affecting the quality of printing are presented. Meets the requirements of the federal state educational standards of higher education of the latest generation. It is intended for teaching students of higher education institutions in the discipline " Flexographic printing technology "in the direction of bachelor's degree 29.03.03 and master's degree 29.04.03" Technology of printing and packaging production", can be used in practical work by specialists of printing enterprises and publishing organizations.

Antimicrobial food packaging involves packaging the foods with antimicrobials to protect them from harmful microorganisms. In general, antimicrobials can be integrated with packaging materials via direct incorporation of antimicrobial agents into polymers or application of antimicrobial coating onto polymer surfaces. The former option is generally achieved through thermal film-making technology such as compression molding or film extrusion, which is primarily suitable for heat-stable antimicrobials. As a nonthermal technology, surface coating is more promising compared to molding or extrusion for manufacturing food packaging containing heat-sensitive antimicrobials. In addition, it also has advantages over direct incorporation to preserve the packaging materials' bulk properties (e.g., mechanical and physical properties) and minimize the amount of antimicrobials to reach sufficient efficacy. Herein, antimicrobial food packaging films achieved through surface coating is explored and discussed. The two components (i.e., film substrate and antimicrobials) consisting of the antimicrobial-coated films are reviewed as plastic/biopolymer films; and synthetic/naturally occurring antimicrobials. Furthermore, special emphasis is given to different coating technologies to deposit antimicrobials onto film substrate. Laboratory coating techniques (e.g., knife coating, bar coating, and spray coating) commonly applied in academic research are introduced briefly, and scalable coating methods (i.e., electrospinning/spraying, gravure roll coating, flexography coating) that have the potential to bring laboratory-developed antimicrobial-coated films to an industrial level are explained in detail. The migration profile, advantages/drawbacks of antimicrobial-coated films for food applications, and quantitative analyses of the reviewed antimicrobial-coated films from different aspects are also covered in this review. A conclusion is made with a discussion of the challenges that remain in bringing the production of antimicrobial-coated films to an industrial level.

Orodispersible film (ODF) formulations are promising and progressive drug delivery systems that are widely accepted by subjects across all the age groups. They are traditionally fabricated using the most popular yet conventional method called solvent casting method. The most modern and evolving method is based on printing technologies and such printed products are generally termed as printed orodispersible films (POFs). This modern technology is well suited to fabricate ODFs across different settings (laboratory or industrial) in general and in a pharmacy setting in particular. The present review provides an overview of various printing methods employed in fabricating POFs. Particularly, it provides insight about preparing POFs using inkjet, flexographic, and three-dimensional printing (3DP) or additive manufacturing techniques like filament deposition modeling, hot-melt ram extrusion 3DP, and semisolid extrusion 3DP methods. Additionally, the review is focused on patenting trends in POFs using ESPACENET, a European Patent Office search database. Finally, the review captures future market potential of 3DP in general and ODFs market potential in particular.

The printing industry all over the world faces a problem of huge amounts of wastage due to a number of reasons, like wastage due to the presence of defects, wastage during machine setup, wastage during packaging and so on. Thus, there is a need for studies focusing on wastage reduction in the printing industry. Amongst the industries, flexographic printing is the most preferred type of printing technology due to its continuous process functionality, technology enhancement for non-porous substrates and its manufacturing flow. This research is focused on managing wastage in flexographic printing industries. The study is concerned about the wastages occurring due to the presence of defects in the output produced. Manufacturing organizations have struggled with the sustenance of quality improvement due to the occurrence of natural and unnatural causes of variation called defects. For achieving maximum improvement, the firms should focus on those defects which are overriding in terms of monetary loss, frequency, the time required for rework, criticality to customer etc. Therefore, the purpose of this paper is to identify the most perilous defects due to which most of the firms in the printing industry are facing rejections. Since the identification of such defects from a list of all possible defects (identified through literature survey and expert interviews) is a multi-criteria problem involving group decision-making, thus in this study, an integrated multi-criteria decision-making (MCDM) approach has been used for defect prioritization. Due to the availability of vague and imprecise data, the fuzzy theory has been adopted with simple additive weighting (SAW) for determining criteria weights and additive ratio assessment (ARAS) for defect prioritization based on experts’ opinions. The results of the study can be used by practitioners for improving the quality of flexographic printing.

The aim of the chapter is to develop an approach for improving quality management in flexographic printing on packages using cognitive agent. A hybrid agents' architecture based on the learning intelligent distribution agent architecture (LIDA) and hierarchical temporal memory has been developed. Such approach has not been developed before; therefore, it is the main contribution of this chapter. The first part of the chapter presents the introduction to the research problem and background. Next, research methodology and the LIDA cognitive agents have been described. The main part of chapter presents the cognitive agent's architecture and functionality related to quality management in flexographic printing. The last part presents discussion, future works, and major conclusions.

Within this work, we provide a comprehensive overview about research activities and current status with respect to rotary printed metallization for silicon solar cells. We will present the major results of the research project »Rock-Star« and previous activities which focused on the metallization of Si solar cells using flexographic printing and rotary screen printing. We demonstrate that the rear side metallization of passivated emitter and rear cells (PERC) can be realized with rotary screen printing on the same quality level as state-of-the-art flatbed screen printing. Furthermore, it is shown that both rotary screen printing and flexographic printing are able to realize the fine line front side metallization. Fine line front side contacts down to approx. 40 µm for rotary screen printing and around 30 µm for flexographic printing are demonstrated. However, further optimization is required to reduce finger width, increase finger height and thus decrease the mean lateral finger resistance. A major result of project »Rock-Star« is the development of an innovative demonstrator platform to enable rotary printed solar cell metallization with high printing speed and low cycle time per wafer. Newly developed transport, alignment and printing concept enables a cycle time of down to 0.45 s/wafer. The concept and features of the demonstrator machine are presented within this paper.

U disertaciji je izvršena karakterizacija sliv nosioca fleksoštamparskih formi i predstavljena su istraživanja uticaja promenemehaničkih i adhezivnih svojstava slivova na parametre kvalitetaštampe kartonske ambalaže. Korišćene su dve grupe samolepljivihslivova (potpuno novi i slivovi korišćeni za štampu 5.000.000 mmaterijala). Ciljevi istraživanja su povećanje predvidivosti ikonstantnosti kvaliteta štampanog proizvoda i procesa proizvodnjekartonske ambalaže, formiranje preporuka za upotrebu slivovarazličitih svojstava i nivoa eksploatisanosti i otkrivanje u kojimfazama i kojim procesima dolazi do promena svojstava slivova., Research presented in this dissertation includes characterization offlexographic sleeves and the study of the influence of the changes inmechanical and adhesive properties of the sleeves on print qualityparameters of the cardboard packaging. Two groups of self-adhesive sleeveswere used (entirely new and sleeves used for printing of 5.000.000 m ofmaterial). Aims of the research are the increase in predictability and stabilityof the printed product quality and the production process of cardboardpackaging, forming of the recommendations for the use of sleeves withdifferent properties and levels of exploitation, as well as defining the phasesand processes responsible for the changes in sleeve properties.

Printable electronics is a promising manufacturing technology for the potential production of low-cost flexible electronic devices, ranging from displays to active wear. It is known that rapid printing of conductive ink on a flexible substrate is vulnerable to several sources of variation during the manufacturing process. However, this process is still not being subjected to a quality control method that is both non-invasive and in situ. To address this issue, we propose controlling the printing accuracy by monitoring the spatial distribution of the deposited ink using terahertz (THz) waves. The parameters studied are the printing speed of an industrial roll-to-roll press with flexography printing units and the pre-calibration compression, or expansion factor, for a pattern printed on a flexible plastic substrate. The pattern, which is carefully selected, has Babinet’s electromagnetic transmission properties in the THz frequency range. To validate our choice, we quantified the geometric variations of the printed pattern by visible microscopy and compared its accuracy using one-dimensional THz spectroscopy. Our study shows a remarkable agreement between visible microscopic observation of the printing performance and the signature of the THz transmission. Notably, under specific conditions, one-dimensional (1D) THz information from a resonant pattern can be more accurate than two-dimensional (2D) microscopy information. This result paves the way for a simple strategy for non-invasive and contactless in situ monitoring of printable electronics production.

Graphene exhibits excellent physical, electronic, and chemical properties that are highly desirable for biosensing applications. However, most graphene biosensors are based on graphene lying flat on a substrate and therefore do not utilize its maximum specific surface area for ultrasensitive detection. Herein, we report the novel use of photonic annealing on a flexographically printed graphene-ethyl cellulose composite to produce vertically aligned graphene (VAG) biosensors for ultrasensitive detection of algal toxins in drinking water. These VAG structures, which maximized the specific surface area of graphene, were formed by partial removal of the polymeric binder upon applying intense pulsed light on the printed graphene. A label-free and low-cost VAG biosensor based on a non-faradaic electrochemical impedance spectroscopy technique was fabricated. The biosensor exhibited a limit of detection of 1.2 ng/L for microcystin-LR in local tap water. Such an ultrasensitive VAG biosensor is suitable for low-cost mass production using an integrated roll-to-roll flexographic printing with rapid photonic annealing technique.

Medical technologies, such as point-of-care devices and biological and chemical assays which rely on functional materials deposited on top of substrates, are in great demand due to an increase in the prevalence of diseases worldwide. A significant number of these medical technologies are still in their infancy with respect to commercialization because of the high cost, material and complexity of the conventionally available fabrication techniques. As a result, medical technologies, in broad terms, require low cost and mass production fabrication methods in order to overcome the commercialization challenges. Recently, researchers have explored the flexographic printing technique which is widely employed for food packaging and newspaper production. This technique has proved cost-effective, facile, rapid and industrially compatible fabrication technique of functional materials for various applications. In this review, we provide an account of the attempts of flexographic printing made to scale up functional materials on surfaces for biomedical applications. Firstly, we offer justification for demanding high-throughput fabrication techniques. We then present the facile working principle of the flexographic printing and its use in different medical applications, for example chronic disease monitoring devices, colorimetric sensors, electrochemical sensors, assays and drugs. Finally, we discuss challenges of the fabrication technique. The main purpose of this review is to give insights into the usefulness of flexographic printing to the health care industry.

Transferring a defined amount of material can have many advantages. In this work, laser-generated microstructures are inserted in plain flexographic printing form material using a femtosecond laser to control the wetting behavior. The results are transferred to a printing form, which is functionalized by inserting these microstructures in the material transferring areas. In this paper, different structures and their effect on the printing results are investigated. Through functionalization of the printing form, not only can the transferred amount of material be adjusted, but also the cross section shape of the printing result. Further, after laser processing and printing, the printing form shows no relevant wear or chemical instabilities.

This paper analyzes an approach for additively manufacturing polymer optical waveguides. The production process includes flexographic printing of conditioning lines (5 μm height) on a substrate, which are used as guiding barriers in the subsequent printing of the optical core. The core is additively printed (up to 50 μm in height) with an aerosol jet printer, filling the gap between the conditioning lines. The conditioning lines do not only enhance the contact angle of the polymer, which results in a higher cross section of the waveguides, but also improve the straight edges of the printed waveguides. We show that the quality of the conditioning lines is directly correlated to the waviness of the waveguides. Consequently, the analyses of the waviness of the conditioning lines classifies the quality of the fabricated waveguides. However, the waviness of the waveguides can also be considered in optical simulations. In this paper we show how we derive a waveguide model with waviness by fitting a single sine function onto the topological data of the conditioning lines. With this model a variation of the waviness can easily be simulated and goals for fabrication can be set. With the simulations it is possible to verify that the measured waviness (period of 559.5 μm and an amplitude of 4.99 μm) does not affect the optical quality of the waveguides.

G7 process is a new calibration method based on GRACOL7 standard. Unlike the traditional process, it is based on the technologies of Computer-to-Plate (CTP) imaging and spectrophotometer detection and the gray balance can be controlled better in offset printing process. G7 process is a revolutionary process from proofing to printing in offset. However, in flexographic printing, the problems of dot gain and small dots losing are more serious and ink layer is thicker than offset printing, which makes tone reproduction in flexographic printing quite different from offset printing. Therefore, the G7 process, which is usually used in offset printing, cannot achieve gray balance. By adjusting the plate making and compensation parameters through experiments, this paper gives a better solution to the color deviation in G7 process, which is used in flexographic printing.

Many different methods, such as screen printing, gravure, flexography, inkjet etc., have been employed to print electronic devices. Depending on the type and performance of the devices, processing is done at low or high temperature using precursor- or particle-based inks. As a result of the processing details, devices can be fabricated on flexible or non-flexible substrates, depending on their temperature stability. Furthermore, in order to reduce the operating voltage, printed devices rely on high-capacitance electrolytes rather than on dielectrics. The printing resolution and speed are two of the major challenging parameters for printed electronics. High-resolution printing produces small-size printed devices and high-integration densities with minimum materials consumption. However, most printing methods have resolutions between 20 and 50 μm. Printing resolutions close to 1 μm have also been achieved with optimized process conditions and better printing technology.

Foaming inks have a wide range of applications in the light industry, mainly including chemical foaming inks and physical foaming inks. The chemical foaming ink was obtained by chemical reaction of a chemical foaming agent to form gas, and the physical foaming ink was obtained by vaporizing the liquid core material in the microcapsule at a certain temperature to generate internal pressure. In this paper, chemical foaming agents and physical foaming microcapsules were used as functional materials. The corresponding foaming ink was obtained by formula design. Meanwhile, the chemical and physical foaming inks were printed by screen, flexo and gravure printing processes, and the printing law was systematically studied. The print abilities of products, including foam height, color and ink adhesion were mainly investigated by different printing methods. The ultimate aim was to provide practical guidance for the foaming ink in the application process of lightweight technology.

Objective: with the premise of printability of graphene ink, the printing technologies with graphene ink are applied in a large scale for printed electronic products, realizing the extensive application of intelligent packaging. Methods: in conjunction with characteristics of graphene ink, this article adopts top-down and bottom-up preparation techniques and produces auxiliary dispersant by using n-methylpyrrolidone (NMP), dimethylformamide (DMF), polyvinylpyrrolidone (PVP), and surfactants for observing the changes of printability of graphene ink. Results: a technological breakthrough has been made in graphic technologies, such as screen printing, gravure printing, flexography, lithography, inkjet printing, and plate making methods in the applications of graphene inks, especially empirical research on micro-contact printing based on flexography has been verified. Conclusion: the discovery of graphene significantly promoted the development of flexible electronics. Green and sustainable graphene ink with excellent conductivity can replace traditional metal components in electronics industry, with promising prospect.

The aim of this work was to study the influence of primary and secondary hydroxyl groups in the branched polyglycerol on the selected properties of water-based printing ink and copies printed with water-based flexographic printing inks. The branched polyglycerols were synthesized through anionic ring-opening polymerization using trimethylolpropane as a starting material. Obtained polyglycerol exhibited an irregular structure containing primary and secondary or predominantly primary hydroxyl groups in the macromolecule. The analysis (FTIR, 1H NMR, 13C NMR) confirmed the structure of polyglycerols. Obtained polyglycerols were then used as a performance additive in a water-based flexographic printing ink. The contact angles of the printing inks on the printing base were measured. The impact of a small amount of branched polyglycerol on the printing ink color was examined by studying the optical density of a full-tone area, the color values (CIELAB), the total color difference $$\Delta E_{ab}^{*}$$ , and gloss of the dried ink film. In general, the addition of branched polyglycerol containing only primary hydroxyl groups improved the wettability of the plastic film and gloss of printing ink with an acceptable total color difference $$\Delta E_{ab}^{*}$$ in contrast to branched polyglycerol with primary and secondary hydroxyl groups.