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Interfacial Adhesion Failure : Impact on print-coating surface defectsKamal Alm, Hajer January 2016 (has links)
The aim of this work was to develop a solid knowledge on formulation effects controlling offset ink-paper coating adhesion and to identify key factors of the coating and printing process affecting it. Focus lay on comprehending the impact of pigment dispersant on ink-paper coating adhesion and ultimately on the print quality of offset prints. The work covers laboratory studies, a pilot coating trial designed to produce coated material with a span in surface chemistry and structure, and an industrial offset printing trial. The lab scale studies quantified ink-paper coating adhesion failure during ink setting with a developed laboratory procedure based on the Ink-Surface Interaction Tester (ISIT) and image analysis. Additional polyacrylate dispersant resulted in slower ink setting and reduced ink-paper coating adhesion, with a dependence on its state of salt neutralisation and cation exchange, mainly in the presence of moisture/liquid water. The industrial printing trial on pilot coated papers was designed to study how these laboratory findings affected full scale offset print quality. These trials confirmed the dispersant-sensitive effect on ink-paper coating adhesion, especially at high water feeds. Evaluation of prints from the printing trial resulted in two fundamentally different types of ink adhesion failure being identified. The first type being traditional ink refusal, and the second type being a novel mechanism referred to as ink-lift-off adhesion failure. Ink-lift-off adhesion failure occurs when ink is initially deposited on the paper but then lifted off in a subsequent print unit. In this work, ink adhesion failure by this ink-lift-off mechanism was observed to occur more often than failure due to ink refusal. Print quality evaluation of the industrial prints suggested that water induced mottle was caused by a combination of ink-surface adhesion failure, creating white spots on the print, together with variation in ink layer thickness due to emulsified ink. / <p>QC 20161019</p>
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Evaluation of Systematic&Colour Print MottleChristoffersson, Jessica January 2005 (has links)
<p>Print mottle is a problem that has been hassling the printing business for a long time. Along with sharpness and correct colour reproduction, absence of print mottle is one of the most important factors of print quality. The possibility to measure the amount of print mottle (reflectance variation) may in many ways facilitate the development of printing methods. Such a measurement model should preferably follow the functions and abilities of the Human Visual System (HVS). </p><p>The traditional model that STFI-Packforsk has developed to measure print mottle uses frequency analysis to find variations in reflectance. However, this model suffers some limitations since is does not perfectly agree with the functions of the HVS and does only measure variations in lightness. A new model that better follows the functions of the HVS has thus been developed. The new model does not only consider variations in lightness (monochromatic) but also variations in colour (chromatic). The new model also puts a higher weight on systematic variations than on random variations since the human eye is more sensitive to ordered structures. Furthermore, the new model uses a contrast sensitivity function that weights the importance of variations in different frequencies. </p><p>To compare the new model with the traditional STFI model, two tests were carried out. Each test consisted of a group of test patches that were evaluated by the traditional STFI model and the new model. The first test consisted of 15 greyscale test patches that originated from conventional flexo and offset presses. The second test consisted of 24 digitally simulated test patches containing colour mottle and systematic mottle. </p><p>The evaluation results in both the traditional and the new model were compared to the results of a visual evaluation carried out using a panel of test persons. The new model produced a result that correlated considerably better with the visual estimation than what the traditional model did.</p>
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INFLOW : Structured Print Job Delivery / INFLOW : strukturerade jobbleveransBuckwalter, Claes January 2003 (has links)
<p>More and more print jobs are delivered from customer to printer digitally over the Internet. Although Internet-based job delivery can be highly efficient, companies in the graphic arts and printing industry often suffer unnecessary costs related to this type of inflow of print jobs to their production workflows. One of the reasons for this is the lack of a well-defined infrastructure for delivering print jobs digitally over the Internet. </p><p>This thesis presents INFLOW - a prototype for a print job delivery system for the graphic arts and printing industry. INFLOW is a web-based job delivery system that is hosted on an Internet-connected server by the organization receiving the print jobs. Focus has been on creating a system that is easy to use, highly customizable, secure, and easy to integrate with existing and future systems from third-party vendors. INFLOW has been implemented using open standards, such as XML and JDF (Job Definition Format). </p><p>The requirements for ease-of-use, high customizability and security are met by choosing a web-based architecture. The client side is implemented using standard web technologies such as HTML, CSS and JavaScript while the serverside is based on J2EE, Java Servlets and Java Server Pages (JSP). Using a web browser as a job delivery client provides a highly customizable user interface and built in support for encrypted file transfers using HTTPS (HTTP over SSL). </p><p>Process automation and easy integration with other print production systems is facilitated with CIP4’s JDF (Job Definition Format). INFLOW also supports"hot folder workflows"for integration with older preflight software and other hot folder-based software common in prepress workflows.</p>
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Hybrid printing on fibre-based packaging : Performance, Quality and MarketRehberger, Marcus January 2010 (has links)
Variable data will play a decisive role in the future of packaging and product promotion. Variable data printing (VDP) is a technique whereby certain information can be altered in an otherwise static layout with the help of a digital printing system, and in the packaging industry a wide range of applications is possible. Inkjet printing, due to its non-impact printing (NIP) principle, is the most suitable technology to use when applying variable data on packaging and to offer customized and even personalized prints for the industry and the end-consumer (van Daele, 2005). The aim of the work described in this thesis was to evaluate the practicability of attaining high quality variable data print (VDP) at high speed. The thesis is divided into three major parts. Part one focussed on the surface topography of corrugated board and applicable analytical methods to describe the printability of the substrate. In the second part the performance of inkjet on corrugated board liners printed at high speed was investigated and how to achieve maximum printing resolution. The final part of the thesis is devoted to a market survey of variable data printing on the North American and European markets. Part 1 concentrated on corrugated board as substrate and its pre-conditions regarding surface topography before the printing operation. Most critical for the quality are print defects such as mottling, gloss and stripiness, all of which occur in the printing of corrugated board. Stripiness is especially critical because it is one of the most disturbing print defects on corrugated board since it is periodical and more easily perceived than random print defects (Netz, 1996). Part 1 revealed that there is a difference in surface micro-roughness between the regions on the peak line of the fluting and the regions in the valley between two peaks of the corrugation which leads to glossy lines on the peak areas. The aim of the second part was to assess the practicability of attaining high quality VDP at high speed on a variety of liners for corrugated board production. The trial was conducted on a Kodak Versamark DP5240 press in Örnsköldsvik, Sweden, in cooperation with the Mid-Sweden University - Digital Printing Centre (DPC). Nine different substrates were printed at speeds between 0.5 and 5 m/s. The results revealed that the paper type rather than the printing speed has the greatest influence on the print quality. Speed, however, is the most important technical factor for inline implementation of inkjet. To obtain a picture of the industries’ view of variable data print on fibre-based packaging, a market survey was initiated and was addressed to people in the development, marketing and decision-making sectors of the packaging and printing industry, including manufacturers of machinery, producers of packaging and prints, and print buyers. The goal was to draw an overview map covering the people’s view of their market, trends in their fields and how they envision the future of VDP on fibre-based packaging. The conclusion was that inkjet technology has to prove itself first and to increase its technical capability, and the printing industry will then start investing more in this technology and in applications such as VDP. / QC 20101206
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Frank Nunan and the Guelph Bookbindery: A Documentary InvestigationGolick, Greta Petronella 15 February 2011 (has links)
The History of the Book in Canada / Histoire du livre et de l’imprimé au Canada and other national book history projects have been a catalyst for research into the local production of print and have highlighted the need for more study of the print trades in smaller centres. In Ontario during the nineteenth century independent weekly newspapers were printed in most villages, while larger towns boasted more than one print shop and often one or more booksellers and stationers. Bookbinders were active members of the book trades selling books and stationery, ruling paper, binding local pamphlets, periodicals, and books, and manufacturing blankbooks for a variety of purposes. Since much local printing was ephemeral in nature, the only evidence of its existence is found in the record books kept by printers and binders. Partial business records and other surviving artifacts of the Guelph Bookbindery, which operated from 1855 to 1978, are both a rich source of evidence of the day-to-day operations of the bookbindery and a key to the intersection of print trades in Guelph, Ontario, and the surrounding counties. This study uses local imprints, blankbooks, authors’ papers, newspapers, directories, maps, assessment records, photographs, museum artifacts, and oral history accounts to reconstruct a history of the bookbindery and its place in the print culture of nineteenth-century Guelph. It documents the transformation of a business selling books, stationery, and wallpaper into a commercial bindery, which along with local printers produced large numbers of pamphlets, ubiquitous then but increasingly rare today. It is a view into the microcosm of a dynamic community where print was a vital medium for communication reflecting the cultural, commercial, and entrepreneurial discourse in nineteenth-century Canadian society that reached far beyond its borders.
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Frank Nunan and the Guelph Bookbindery: A Documentary InvestigationGolick, Greta Petronella 15 February 2011 (has links)
The History of the Book in Canada / Histoire du livre et de l’imprimé au Canada and other national book history projects have been a catalyst for research into the local production of print and have highlighted the need for more study of the print trades in smaller centres. In Ontario during the nineteenth century independent weekly newspapers were printed in most villages, while larger towns boasted more than one print shop and often one or more booksellers and stationers. Bookbinders were active members of the book trades selling books and stationery, ruling paper, binding local pamphlets, periodicals, and books, and manufacturing blankbooks for a variety of purposes. Since much local printing was ephemeral in nature, the only evidence of its existence is found in the record books kept by printers and binders. Partial business records and other surviving artifacts of the Guelph Bookbindery, which operated from 1855 to 1978, are both a rich source of evidence of the day-to-day operations of the bookbindery and a key to the intersection of print trades in Guelph, Ontario, and the surrounding counties. This study uses local imprints, blankbooks, authors’ papers, newspapers, directories, maps, assessment records, photographs, museum artifacts, and oral history accounts to reconstruct a history of the bookbindery and its place in the print culture of nineteenth-century Guelph. It documents the transformation of a business selling books, stationery, and wallpaper into a commercial bindery, which along with local printers produced large numbers of pamphlets, ubiquitous then but increasingly rare today. It is a view into the microcosm of a dynamic community where print was a vital medium for communication reflecting the cultural, commercial, and entrepreneurial discourse in nineteenth-century Canadian society that reached far beyond its borders.
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Tourist : An investigation of the printed Hawaii shirt / Turist : En undersökning av den mönstrade HawaiiskjortanSjögren, Linn January 2018 (has links)
The aim of this work is to explore the printed Hawaii shirt through material investigations in search of new print meetings. A vital step for this investigation was to develop the classic Hawaii- prints and motives in mixed media. Followed by exploring alternative printing techniques such as transfer printing, laser cutting and knitting in different materials to reach new expressions yet keeping a clear reference to the Hawaii shirt. The intention of this work was to investigate how the Hawaii shirt with its classic print could interact with the mind and body of the wearer. Furthermore, to question the informal rules of wearing a Hawaii shirt with a starting point in Umberto Eco’s theories about epidemic self-awareness. The motive of this work is to critically look at the society today, with a focus on consumerism, foreign travel and tourism and the expression of it, with the Hawaii shirt as a symbol of these things. Based on the assumption of the Hawaii shirt being a tacky souvenir that tourists bring back home from their holidays. This work show new expressions of the printed Hawaii shirt through innovative print meetings. This work also proposes alternative ways of wearing a Hawaii Shirt.
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Evaluation of Systematic&Colour Print MottleChristoffersson, Jessica January 2005 (has links)
Print mottle is a problem that has been hassling the printing business for a long time. Along with sharpness and correct colour reproduction, absence of print mottle is one of the most important factors of print quality. The possibility to measure the amount of print mottle (reflectance variation) may in many ways facilitate the development of printing methods. Such a measurement model should preferably follow the functions and abilities of the Human Visual System (HVS). The traditional model that STFI-Packforsk has developed to measure print mottle uses frequency analysis to find variations in reflectance. However, this model suffers some limitations since is does not perfectly agree with the functions of the HVS and does only measure variations in lightness. A new model that better follows the functions of the HVS has thus been developed. The new model does not only consider variations in lightness (monochromatic) but also variations in colour (chromatic). The new model also puts a higher weight on systematic variations than on random variations since the human eye is more sensitive to ordered structures. Furthermore, the new model uses a contrast sensitivity function that weights the importance of variations in different frequencies. To compare the new model with the traditional STFI model, two tests were carried out. Each test consisted of a group of test patches that were evaluated by the traditional STFI model and the new model. The first test consisted of 15 greyscale test patches that originated from conventional flexo and offset presses. The second test consisted of 24 digitally simulated test patches containing colour mottle and systematic mottle. The evaluation results in both the traditional and the new model were compared to the results of a visual evaluation carried out using a panel of test persons. The new model produced a result that correlated considerably better with the visual estimation than what the traditional model did.
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INFLOW : Structured Print Job Delivery / INFLOW : strukturerade jobbleveransBuckwalter, Claes January 2003 (has links)
More and more print jobs are delivered from customer to printer digitally over the Internet. Although Internet-based job delivery can be highly efficient, companies in the graphic arts and printing industry often suffer unnecessary costs related to this type of inflow of print jobs to their production workflows. One of the reasons for this is the lack of a well-defined infrastructure for delivering print jobs digitally over the Internet. This thesis presents INFLOW - a prototype for a print job delivery system for the graphic arts and printing industry. INFLOW is a web-based job delivery system that is hosted on an Internet-connected server by the organization receiving the print jobs. Focus has been on creating a system that is easy to use, highly customizable, secure, and easy to integrate with existing and future systems from third-party vendors. INFLOW has been implemented using open standards, such as XML and JDF (Job Definition Format). The requirements for ease-of-use, high customizability and security are met by choosing a web-based architecture. The client side is implemented using standard web technologies such as HTML, CSS and JavaScript while the serverside is based on J2EE, Java Servlets and Java Server Pages (JSP). Using a web browser as a job delivery client provides a highly customizable user interface and built in support for encrypted file transfers using HTTPS (HTTP over SSL). Process automation and easy integration with other print production systems is facilitated with CIP4’s JDF (Job Definition Format). INFLOW also supports"hot folder workflows"for integration with older preflight software and other hot folder-based software common in prepress workflows.
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Změna vlastnických struktur českých médií na počátku 21.století - návrat do rukou domácích vlastníků / Transformation of the czech media ownership structures in the early 21 centuryVojtová, Magdaléna January 2017 (has links)
The primary goal of this master thesis was to analyze the development of ownership of daily newspapers in the Czech Republic in the period 2008 - 2016. The development of media ownership in the monitored period was analyzed in the context of the long term structural problems of media sector, which were intensified by the economic crisis beginning in 2008. In addition to the economic context, the thesis also deals with the historical context, specifically the changes of the Czech daily newspapers market after 1989. In connection with the transfer of ownership of the Czech publishing houses to the hands of domestic businessmen, often with direct links to politics, thesis also deals with the issue of ownership concentration and the relations between media and politics. I also mention the phenomenon of emerging new, alternative media projects by the journalists in reaction to ownership changes threatening pluralism and freedom of speech. In the end, I also compare the development of ownership of the daily newspapers in the Czech Republic with the development of ownership in other countries of the CEE region, such as Slovakia, Poland, Hungary or the Baltic States.
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