Academic literature on the topic 'Flexo printing'

During the flexo printing process of corrugated flexible resin version, precise pressure control is the key technical indicators of ink transfer, printing graphic reproduction as well as reducing the the loss of physical properties of corrugated board. The gaps △L between the printing roller and the impression cylinder were adjusted by the worm in this paper, different printing pressures are produced in the printing process, the impact of pressure change on flexo printing quality was described quantitatively. The results showed that: 7.5mm thick corrugated board used AB-type hardness of 36 Shore A, when a thickness of 3.94mm DuPont flexible resin was printed, the optimal pressure gap △L was 10.9mm, the flexible resin version of the real size was 3.73mm, and the thickness of corrugated board was 7.17mm, the board thickness was 7.30mm after decompression, the thickness of corrugated board after the printing was compressed by 2.7%. The result of this paper offers a certain theoretical reference and practical guidance to improve the quality of flexo and the production of high quality corrugated board.

With the development of printing technology, greater emphasis has been laid on environmentally friendly materials. Due to its printability and environmental friendliness, Water-based flexo ink is gradually gaining popularity at home and abroad, and has been widely applied in the field of printing. Different from other kinds of bills, scratch-type invoices have an additional scratch area on the surface, which highly covering performance is required for the ink applied. This paper emphatically analyzes and discusses: (a) flexo water-based covering ink and its application in scratch-type invoice covering region printing; (b) how to explore and evaluate new developed green inks. Compared with traditional inks, the water-based flexo ink is free of emissions of volatile organic compounds (VOC), and its popularization might have significant meanings for the environment protection and sustainable development.

We considered pattern formation, i.e. viscous fingering, in the ink splitting process between an elastic flexographic printing plate and the substrate. We observed an unexpected scaling behavior of the emerging pattern length scale (i.e., finger width) as a function of printing velocity, fluid viscosity, surface tension, and plate elasticity coefficients. Scaling exponents depended on the ratio of the capillary number of the fluid flow, and the elastocapillary number defined by plate elasticity and surface tension. The exponents significantly differed from rigid printing plates, which depend on the capillary number only. A dynamic model is proposed to predict the scaling exponents. The results indicate that flexo printing corresponded to a self-regulating dynamical equilibrium of viscous, capillary, and elastic forces. We argue that these forces stabilize the process conditions in a flexo printing unit over a wide range of printing velocities, ink viscosities, and mechanical process settings.

In the Printing Industry, printing inks, varnishes, lacquers, moistening solutions and washing solvents (ethanol, methyl acetate, ethyl acetate, isopropanol, n-propanol, hexane, benzene, toluene, xylene, isopropyl acetate, propyl acetate, dimethyl ketone, glycols and glycol ethers) contain volatile organic compounds (VOCs) and air pollutants (HAPs). Especially solvent based inks used for flexo, gravure and screen printing, offset printing dampening solutions and cleaning solvents contain high concentration of VOC. These organic compounds evaporate during the production process or contribute to the photochemical reaction. VOCs and HAPs, together with sunlight and nitrogen oxides, cause photochemical smoke, air particles and ground level ozone emission in the atmosphere. The VOCs and heavy metals can lead to soil and even water pollution when left in landfill. The amount of solvent retained by flexo, gravure and screen-printed products is 3-4% of total ink solvent used. The solvent in the printed ink content, except for the one held by the printed material evaporates in its own environment after the printing process. Most of these solvents and organic compounds used in printing environment contain at least one carbon and hydrogen atom and have negative effects on health and environment.In this study, the environmental impacts and risks of inks and solvents used in the printing industry have been evaluated. Measures to be taken to reduce and manage these environmental effects and risks have been addressed and recommendations have been made.

Roll to roll process is one of the famous printing techniques that are possible to create graphic and electronic device on variable substrate by using conductive ink. Graphene is an example of material that can be used as printing ink which usually used in producing micro-scale electronic devices. Here, it is proposed that extending roll to roll printing technique into the multiple micro-scale printing fine solid line onto substrate by using graphene as a printing ink. Flexography is a high speed roll to roll printing technique commonly used in paper printing industry. And this study elaborates the feasibility of graphene as a printing ink use in combination of flexography and micro-contact or micro-flexo printing for micro fine solid line. This paper will illustrates the review of graphene in producing multiple micro-solid lines printing capability for the application of printing electronic, graphic and bio-medical.

The article covers the research on the changing of flexo plates' deformation properties during swelling in various solvents that are used in the printing industry. The acquired data was processed with the equation from the Kelvin-Voigt model, the constant models and times of relaxation of the initial and swelled photopolymer have been determined.

Heterogeneous Fenton catalyst Fe2(MoO4)3 was prepared and the process efficiency was evaluated for oxidation of water-based Cyan flexo dye in synthetic aqueous solution and printing wastewater. The removal process of printing dye was analyzed by UV/VIS spectrophotometry, while dye mineralization was evaluated by the determination of total organic carbon content and chemical oxygen demand. Four determinants of the heterogeneous Fenton system, including initial dye concentration, iron concentration, pH and hydrogen peroxide concentration were investigated. Statistical method, definitive screening design was applied to generate optimal operational conditions of the four variables, which maximizes the process of dye removal. The initial dye concentration of 20 mgL-1, catalyst dosage of 0.75 mgL-1, pH of 2 and H2O2 concentration of 11 mM were chosen as the best operational conditions, contributing to 82% of the process efficiency. The Fenton process efficiency of 79% was achieved within the treatment of printing wastewater under optimal conditions for a 90 minute reaction time. The maximum COD removal efficiency was 61.1%, while 67% mineralization was achieved. The obtained results confirmed synergistic effect of Fe3+ and MoO4 2? which contributed to high catalytic activity and high heterogeneous Fenton efficiency.

Im Rahmen der vorliegenden Arbeit wurden Schottky-Dioden mittels Rolle-zu-Rolle-Verfahren hergestellt und charakterisiert. Die Dioden bestanden dabei aus einer Kathode (Aluminium oder Kupfer), die durch Sputtern aufgebracht wurde, einer Halbleiterschicht aus Polytriphenylaminen (PTPA3), die mittels Tiefdruck aufgebracht wurde und einer im Flexodruck hergestellten Anode (PEDOT:PSS, Pani oder Carbon Black). Aus elektrischer Sicht wiesen dabei Dioden mit Kupfer und Carbon Black die besten Eigenschaften auf. Mit Hilfe dieser Elektrodenmaterialien und bei Halbleiterschichtdicken von ca. 200 nm konnten Grenzfrequenzen der Dioden von über 1 MHz realisiert werden. Weiterhin wiesen diese Dioden eine gute Langzeitstabilität sowie eine gute Stabilität gegenüber UV-Licht, Feuchtigkeit und Temperatur auf
Aim of this work was to demonstrate that Schottky-Diodes can be fabricated by means of Roll-to-Roll-Methods and to characterize these diodes. The diodes consists of a sputtered cathode (Aluminum or Copper), a gravure printed semiconducting layer of Polytriphenylamine (PTPA3) and a flexo printed anode (PEDOT:PSS, Pani, Carbon Black). Best electrical characteristics were obtained with diodes consisting Copper and Carbon Black as electrodes. With a thickness of the semiconducting layer of ~200 nm diodes with a cut-off frequency above 1 MHz could be demonstrated. These diodes showed also a good stability when exposed to UV-light, moisture and temperature

碩士
逢甲大學
工業工程與系統管理學研究所
97
The competition in the current world market has forced the manufacturers to produce products with low cost, high quality and matching the environmental protection demand. Friendly production environment, high quality and high efficiency are crucial factors in printing industry. Ultraviolet (UV) printing can match this demand. The UV dosage energy is the most important factor to print high quality product with high production rate. The larger UV dosage energy, the better the printing quality is. The purpose of this research is to improve the dosage energy by randomized complete block design. Two factors are reflector width and the height between lamp and substrate. The blocking factor is the measuring point (left, center and right) of the input material. The results show that the blocking factor is the most significant factor. It is obviously that the center point is much larger than the other two sides. Besides, the height and the interaction of height and reflector width have minor effect. Finally, the optimal parameter design is to change the distance from 78MM to 76MM and the reflector width remain as initial setting. The dosage energy is improved from 281mJ/cm2 to 306mJ/cm2 after the experiment. Thus, the UV Flexo printing quality is improved.

Im Rahmen der vorliegenden Arbeit wurden Schottky-Dioden mittels Rolle-zu-Rolle-Verfahren hergestellt und charakterisiert. Die Dioden bestanden dabei aus einer Kathode (Aluminium oder Kupfer), die durch Sputtern aufgebracht wurde, einer Halbleiterschicht aus Polytriphenylaminen (PTPA3), die mittels Tiefdruck aufgebracht wurde und einer im Flexodruck hergestellten Anode (PEDOT:PSS, Pani oder Carbon Black). Aus elektrischer Sicht wiesen dabei Dioden mit Kupfer und Carbon Black die besten Eigenschaften auf. Mit Hilfe dieser Elektrodenmaterialien und bei Halbleiterschichtdicken von ca. 200 nm konnten Grenzfrequenzen der Dioden von über 1 MHz realisiert werden. Weiterhin wiesen diese Dioden eine gute Langzeitstabilität sowie eine gute Stabilität gegenüber UV-Licht, Feuchtigkeit und Temperatur auf.:Inhaltsverzeichnis 1 Einleitung 2 Metall-Halbleiter-Kontakt 2.1 Idealer Metall-Halbleiter-Kontakt 2.2 Metall-Halbleiter-Kontakt unter Spannung 2.3 Realer Metall-Halbleiter-Kontakt 2.3.1 Metall-Halbleiter-Kontakte ohne Grenzflächenzustände innerhalb der Bandlücke 2.3.2 Metall-Halbleiter-Kontakt mit Grenzflächenzuständen 2.4 Grenzflächen zwischen Metallen und organischen Materialien 2.5 Transportmechanismen / -modelle 2.5.1 Ladungstransport in organischen Halbleitern 2.5.2 Thermionische Emission 2.5.3 Fowler-Nordheim-Tunneln 2.5.4 Raumladungsbegrenzte Ströme 2.6 Poole-Frenkel Effekt 3 Stabilität organischer Materialien 3.1 Einfluss von Sauerstoff 3.2 Einfluss von Wasser 3.3 Einfluss von chemischen Reaktionen 3.4 Einfluss von elektrischem Stress 3.5 Einfluss von Licht 3.6 Einfluss von Struktur- und Morphologieänderungen 3.7 Einfluss von kombinierten Effekten 3.8 Einfluss von Barriereschichten 4 Schottky-Dioden 4.1 Allgemeiner Aufbau 4.2 Stand der Technik 4.3 Anforderungen an Materialien für Schottky-Dioden 4.3.1 Kathode 4.3.2 Halbleiter 4.3.3 Anode 4.4 Gleichrichter 4.5 Logische Schaltungen mit Dioden 5 Rolle-zu-Rolle-Verfahren / Druckverfahren 5.1 Übersicht Druckverfahren / Beschichtungsverfahren 5.2 Bewertung der Verfahren für die Herstellung von Schottky-Dioden 6 Versuchsdurchführung 6.1 Druckversuche 6.1.1 Genutzte Druckmaschinen 6.1.2 Verwendete Materialien 6.2 Messverfahren 6.2.1 Morphologische Charakterisierung 6.2.2 Elektrische Charakterisierung 6.2.3 Strom-Spannungs-Charakterisitik 6.2.4 Kapazitätscharakteristik 6.2.5 Elektrische Eigenschaften der Anodenmaterialien 7 Ergebnisse der Druckversuche 7.1 Einfluss der Lösungsmittel 7.2 Einfluss der Druckgeschwindigkeit 7.3 Druck der Anode 8 Elektrische Charakterisierung der Dioden 8.1 Vergleich der Elektrodenmaterialien 8.2 Strom-Spannungs-Kennlinie in Sperrrichtung 8.3 Gleichmäßigkeit der Strom-Spannungs-Charakteristik 8.4 Einfluss des Lösungsmittelgemischs 8.5 Einfluss der Trocknungstemperatur 8.6 Kapazitätscharakteristika 9 Stabilität 9.1 Langzeitstabilität 9.2 Hysterese 9.3 Einfluss der Temperatur 9.4 Einfluss von Feuchtigkeit 9.5 Einfluss von Licht 9.6 Einfluss von elektrischem Stress 10 Anwendungen 10.1 Gleichrichter 10.2 Logische Schaltungen mit Dioden 11 Zusammenfassung Literaturverzeichnis Abbildungsverzeichnis Tabellenverzeichnis Formel- und Symbolverzeichnis Abkürzungsverzeichnis Danksagung Lebenslauf Veröffentlichungen Eigenständigkeitserklärung
Aim of this work was to demonstrate that Schottky-Diodes can be fabricated by means of Roll-to-Roll-Methods and to characterize these diodes. The diodes consists of a sputtered cathode (Aluminum or Copper), a gravure printed semiconducting layer of Polytriphenylamine (PTPA3) and a flexo printed anode (PEDOT:PSS, Pani, Carbon Black). Best electrical characteristics were obtained with diodes consisting Copper and Carbon Black as electrodes. With a thickness of the semiconducting layer of ~200 nm diodes with a cut-off frequency above 1 MHz could be demonstrated. These diodes showed also a good stability when exposed to UV-light, moisture and temperature.:Inhaltsverzeichnis 1 Einleitung 2 Metall-Halbleiter-Kontakt 2.1 Idealer Metall-Halbleiter-Kontakt 2.2 Metall-Halbleiter-Kontakt unter Spannung 2.3 Realer Metall-Halbleiter-Kontakt 2.3.1 Metall-Halbleiter-Kontakte ohne Grenzflächenzustände innerhalb der Bandlücke 2.3.2 Metall-Halbleiter-Kontakt mit Grenzflächenzuständen 2.4 Grenzflächen zwischen Metallen und organischen Materialien 2.5 Transportmechanismen / -modelle 2.5.1 Ladungstransport in organischen Halbleitern 2.5.2 Thermionische Emission 2.5.3 Fowler-Nordheim-Tunneln 2.5.4 Raumladungsbegrenzte Ströme 2.6 Poole-Frenkel Effekt 3 Stabilität organischer Materialien 3.1 Einfluss von Sauerstoff 3.2 Einfluss von Wasser 3.3 Einfluss von chemischen Reaktionen 3.4 Einfluss von elektrischem Stress 3.5 Einfluss von Licht 3.6 Einfluss von Struktur- und Morphologieänderungen 3.7 Einfluss von kombinierten Effekten 3.8 Einfluss von Barriereschichten 4 Schottky-Dioden 4.1 Allgemeiner Aufbau 4.2 Stand der Technik 4.3 Anforderungen an Materialien für Schottky-Dioden 4.3.1 Kathode 4.3.2 Halbleiter 4.3.3 Anode 4.4 Gleichrichter 4.5 Logische Schaltungen mit Dioden 5 Rolle-zu-Rolle-Verfahren / Druckverfahren 5.1 Übersicht Druckverfahren / Beschichtungsverfahren 5.2 Bewertung der Verfahren für die Herstellung von Schottky-Dioden 6 Versuchsdurchführung 6.1 Druckversuche 6.1.1 Genutzte Druckmaschinen 6.1.2 Verwendete Materialien 6.2 Messverfahren 6.2.1 Morphologische Charakterisierung 6.2.2 Elektrische Charakterisierung 6.2.3 Strom-Spannungs-Charakterisitik 6.2.4 Kapazitätscharakteristik 6.2.5 Elektrische Eigenschaften der Anodenmaterialien 7 Ergebnisse der Druckversuche 7.1 Einfluss der Lösungsmittel 7.2 Einfluss der Druckgeschwindigkeit 7.3 Druck der Anode 8 Elektrische Charakterisierung der Dioden 8.1 Vergleich der Elektrodenmaterialien 8.2 Strom-Spannungs-Kennlinie in Sperrrichtung 8.3 Gleichmäßigkeit der Strom-Spannungs-Charakteristik 8.4 Einfluss des Lösungsmittelgemischs 8.5 Einfluss der Trocknungstemperatur 8.6 Kapazitätscharakteristika 9 Stabilität 9.1 Langzeitstabilität 9.2 Hysterese 9.3 Einfluss der Temperatur 9.4 Einfluss von Feuchtigkeit 9.5 Einfluss von Licht 9.6 Einfluss von elektrischem Stress 10 Anwendungen 10.1 Gleichrichter 10.2 Logische Schaltungen mit Dioden 11 Zusammenfassung Literaturverzeichnis Abbildungsverzeichnis Tabellenverzeichnis Formel- und Symbolverzeichnis Abkürzungsverzeichnis Danksagung Lebenslauf Veröffentlichungen Eigenständigkeitserklärung

In this study we have aimed to present statistical evaluation of changes in the surface roughness of the solid tone areas on CtP flexo printing plate in dependence of print run. Changes in flexo plate surface roughness is influenced by the plate-making process, printing pressure and speed, the interaction with the ink and printing substrate and by the wear of the printing plate due to long print-runs. Thus, the aim of this research was to evaluate the changes in the amplitude surface roughness parameters (Ra, Rp, Rv and Rz), between the printing plates used for different print runs. In the experiment, we have employed three sets of CtP flexo printing plates, for three colors-cyan, magenta and blue. The first set was not used for printing, the second was used to print 7 rolls of substrate and the third is used to print 11 rolls of printing substrate. The amplitude surface roughness parameters were compared by applying independentsamples t-test method using the software SPSS (Statistical Package for Social Science) with a 0.05 significance level. Statistical analysis revealed that the difference between the amplitude surface roughness parameters measured on CtP flexo printing plates are significant with a 95% confidence level, whereas the statistical significance pointed out that with the longer print runs, the difference will be strongly expressed.

Specialty luxury label papers mainly are results from the search for all that stimulates our creativity and senses. They are from papers that awaken the desire to create, as a magnificent mix of texture and colours that elevates luxury packaging to the category of art and a brilliant collection that ultimately shows that luxury packaging really is. In order to achieve the desired complex effect on the customer with its combined impact through the texture, colour of the paper and graphic design for each manufacturer of luxury labels, it is undoubtedly essential to be familiar with the printability of the paper used. The aim of the present work was to study the main properties of the commonly used papers for printing of self-adhesive labels, in view of their printability. It is especially important for the production, as well as for the awareness of the designers working in this field, to know the specifics of these papers, to know the main indicators influencing their printability, to know all the facts allowing the right choice of printing technology and finishing processes. To achieve this goal, various properties of five types of paper have been determined: structural-dimensional, physical-mechanical, capillary-hygroscopic and optical. In addition, with all paper analysis, a printing sample have been made with different types of printing (offset UV, flexo UV, screen, cold foil, hot foil, silk foil) and converting (emboss, laser cutting, laser engraving) techniques. Based on the obtained results, new designer labels for wine have been printed. The results show that there is a clear dependence between the paper composition, its main and specific properties and the quality of the different printing and finishing processes, as well as the overall appearance of the produced labels. The printing and finishing processes have been carried out in Rotoprint Printing House, Bulgaria and the obtained results could give a valuable information not only for the particular printing house, but for other specialists in the field of labels production.

New 3D printing materials are currently being developed and released at a rapid pace, including flexible plastic filament that was recently introduced to the desktop 3D printing market. Flex. Molds explores the potential of using this material in conjunction with standard 3D printing techniques to improve the conventional fabrication process of precast concrete. It poses the question: can 3D printing formwork for concrete alleviate some of the problems associated with traditional casting by reducing fabrication steps and increasing geometric flexibility?