A final word from the editors
This issue of the Journal of Print and Media Technology Research closes its third full year of publication. It also marks the end of my period as Editor-in-Chief. After having successfully established the Journal of Print and Media Technology Research as a high quality scientific journal in the broad field of print and media technology and seen it develop during the first busy years, I now feel that it is time to pass on the responsibility into younger, fresher hands.
We have succeeded in finding an excellent successor in Dr. Gorazd Golob at the University of Ljubljana. He will take over as Editor-in-Chief on January 1, 2015. At the same time, the responsibility for editing the Topicalities section will be assigned to Dr. Markéta Držková at the University of Pardubice.
At first, very little will change. The e-mail address firstname.lastname@example.org will remain but will be assigned to Dr. Golob instead of to me. The stated mission of the journal and the broad variety in its contents will remain unchanged. But, as time goes by, I am certain that Dr. Golob and his team will implement many changes and improvements to the journal.
I wish the new editor and his staff many exciting hours and inspiring experiences in producing the journal, while serving the entire research community and related industries. I trust that all authors and journal readers will continue to support the new editorial team as you have supported me and the current team.
For my part, I would like to sincerely thank all of you who have made this journal possible: the authors, the reviewers, the Scientific Advisory Board, my colleagues on the Editorial Board, the publisher, iarigai, and its Management Board, our former Associate Editor Dr. Raša Urbas, and finally our untiring Executive Editor, Prof. Mladen Lovreček. Thank you all for your enthusiastic cooperation!
Launching a new peer-reviewed journal was an unprecedented experience and challenge, especially in fields that have not been adequately covered with too much publishing opportunities.
A number of high quality papers, that have been presented on iarigai conferences, but also scattered in other different publications, many young, ambitious and capable researchers that emerged throughout the years, all this indicated the need of offering a completely new publishing channel to the research community.
It took more than three long years from the first decision of the Board of iarigai until the first issue of JPMTR was presented in Budapest, in September 2011. It was a period of considering and creating the scope of the new journal, designing its pages, gathering a team of editors and reviewers, resolving many expected problems and anticipating the new ones. Many barriers had to be overcome – external as well as internal – before the first issue was ready for the public.
All this would not be possible without full support of the members and the Board, and of course, without the financial resources of the Association. We believe that his support will remain as firm and undisputed as it was during our tenure.
Although published by iarigai, from the very beginning JPMTR was intended as a journal for wider audience, not only the members. Following the highest standards of scientific editing and publishing, as well as ethic standards, JPMTR has established itself as a reliable source of scientific information. We are sure that it will continue to develop in this way under the new Editor-in-Chief and his team.
Finally, behind each successful project are not only good wishes, enthusiasm, positive aims and possible results, but much more than that, people. It would be a long list of those who contributed in one or another way to the initial success of JPMTR, and our appreciation goes to each of them. The doors are now open wide for the new and better future of a journal.
Helsinki-Zagreb, December 2014
JPMTR 047 ⎮ 1408 Research paper
Developing a high throughput printing technology for silicon solar cell front side metallisation using flexography
Andreas Lorenz1, Andre Kalio1, Tobias Barnes Hofmeister1, Achim Kraft1, Jonas Bartsch1, Florian Clement1, Holger Reinecke2, Daniel Biro1
1 Fraunhofer ISE, Heidenhofstraße 2, D-79110 Freiburg, Germany; E-mails: email@example.com; firstname.lastname@example.org; email@example.com; firstname.lastname@example.org; email@example.com; firstname.lastname@example.org; email@example.com
2 Albert-Ludwigs-Universität, Institut für Mikrosystemtechnik – IMTEK, Georges-Köhler-Allee 103 D-79110 Freiburg, Germany; E-mail: firstname.lastname@example.org
Most crystalline silicon solar cells feature a front and rear side metallisation, which is usually applied by flatbed screen printing. Rotational printing methods represent a highly interesting alternative approach to realize the front side metallisation with a considerably higher throughput. Particularly flexographic printing has proven to be well-suited for fine line contact fingers down to 25 µm width on textured silicon wafers. Within this work, flexographic printing has been applied for a seed layer front side metallisation of silicon solar cells. Three silver based inks with varying viscosity have been prepared for the experiment. Printing tests have been carried out to investigate the impact of printing pressure, material tolerances and ink viscosity on the printed contact finger width. A considerable impact of material tolerances on the printing result has been observed. It was further found that a variation of the ink viscosity did not significantly influence the finger width. Fingers down to a minimum width of 32 µm have been achieved by applying the optimum process parameters. Fully functional solar cells have been produced by reinforcing the flexo printed seed layer metallisation with silver light-induced plating. The solar cells revealed very promising results with a maximum conversion efficiency of η = 18.8 %.
Keywords: flexographic printing, rotational printing, silicon solar cell, solar cell metallisation, seed layer, seed and plate, light induced plating
JPMTR 048 ⎮ 1427 Research paper
Performance optimization of fully printed primary (ZnMnO2) and secondary (NiMH) batteries
Michael Wendler1, 2, 3, Tim Claypole1, Erich Steiner2, Martin Krebs3
1 Welsh Centre for Printing and Coating, Swansea University, Singleton Park, Swansea, SA2 8PP, United Kingdom; E-mails: email@example.com; firstname.lastname@example.org
2 Media University Stuttgart, Nobelstraße 10, D-70569 Stuttgart, Germany; E-mail: email@example.com
3 VARTA Microbattery GmbH, Daimlerstraße 1, D-73479 Ellwangen, Germany; E-mail: firstname.lastname@example.org
Printed batteries, based on nickel/metal hydride and traditional zinc/manganese dioxide chemistry, were manufactured as single cells in stacked configuration by screen printing. To identify the performance limiting elements of the printed rechargeable battery, a printed Ni/MH battery equipped with a Zn-probe was assembled. The printed batteries were electrochemically analyzed by means of electrochemical impedance spectroscopy in two-electrode configuration and by chronopotentiometry. It was demonstrated that the cathode is responsible for the limitations on battery performance. The influences of the limitations of the cathode inks were examined and new water-based electrode inks were developed. The improvement of the electrode inks decreased the overall impedance and raised the value for the open circuit voltage as well as the operating voltage for the primary battery chemistry. In addition to the electrode optimizations, a printable electrolyte/separator paste, equal in its performance to a conventional electrolyte saturated polymer fleece, was developed, enabling a fully printed battery system.
Keywords: printed battery, electrochemical impedance spectroscopy, probe cell, printable electrolyte
JPMTR 049 ⎮ 1438 Research paper
Increased performance of printed electroluminescent devices using a transparent conductive laminate
Daniel Bryant1, Peter Greenwood1, Joel Troughton1, Trystan Watson1, Eifion Jewell2, David Worsley1
1 Baglan Bay Innovation Centre, Baglan Energy Park Baglan, Port Talbot, SA12 7AX, United Kingdom
2 Welsh Centre for Printing and Coating, Swansea University, Singleton Park, Swansea, United Kingdom; E-mail: email@example.com
The paper describes the development of a novel thick film top emission electroluminescent (EL) lamp which displays excellent performance and is fabricated without an ITO film and is encapsulated for safe use. The conductive adhesive laminate can be applied to low cost opaque substrates such as paper. The development utilises a commercial contact adhesive which has been blended with a PEDOT:PSS solution to form a liquid which can be coated onto a conductively micro-structured PET film. This PET film can then be applied under minimal pressure to the EL lamp, to provide a laminated top electrode. An optimization of the material formulation and deposition thickness was required in to order the balance the primary requirements of the coating; namely adhesive tack, conductivity (lateral and through film) and optical transparency. For example, a pure adhesive layer would achieve excellent adhesion but would not be conductive while a pure PEDOT:PSS layer would provide the necessary conductivity but lack any adhesive properties. Non-optimised light output achieved 88 % of that of conventional glass devices and this could be further optimised through manipulation of the PEDOT:PSS concentration and film thickness to create devices with an output of 96 % of that of conventional devices. The optimum balance was found to be a 15 μm film with a 1.25 % concentration of PEDOT:PSS in the adhesive. This material and specification is screen printable, thus the entire material stack can be manufactured using a common single low cost printing process. In order to examine whether silver could be replaced in the manufacture, lamps were manufactured on an aluminium substrate. These achieved 87 % of the light output of conventional lamps although they showed a variability which was associated with the fragility of the substrate and its subsequent variation in flatness during lamp manufacture. The work has shown that EL lamps can be printed that are self-encapsulating and possess a performance close to that of conventional bottom emission lamps.
Keywords: electroluminescence, transparent conductive, adhesive
JPMTR 050 ⎮ 1414 Research paper
The effects of substrate correction on printing conformity
Robert Chung1 and Li Wu2
1 RIT School of Media Sciences, Lomb Memorial Drive, Rochester, NY 14623, USA; E-mail: firstname.lastname@example.org 69
2 Shenzhen Polytechnic, Shenzhen, PR China; E-mail: email@example.com
Printing has become more and more of a manufacturing process. As a manufacturing process, the goal is to meet specifications. When printing on nonconforming papers, printing conformity is jeopardized. The use of the substrate-corrected colorimetric aims (SCCA), as specified in ISO 13655, represents a solution. But benefits of SCCA are not fully understood and the solution not widely adopted in the printing industry. A research question arises: “What is the effect of substrate correction on dataset conformity for a large number of offset, digital printing, and proofing jobs?” To answer the question, this research uses a database of 60 jobs to study the effect of substrate correction on printing conformity where the white points of the dataset and the color of the printing paper vary. The results show that substrate-corrected color aims (SCCA) enable more job conformance and reduce failed jobs for both conforming and non-conforming papers.
Keywords: printing standards, substrate correction, printing conformity
JPMTR 051 ⎮ 1412 Research paper
Dynamics of ink absorption of packaging paper
Li Yang1, Jianghao Liu2, and Xin Li2
1 Innventia AB, Drottning Kristinas väg 61 S-11486 Stockholm, Sweden; E-mail: firstname.lastname@example.org
2 Beijing Institute of Graphic Communication, 1 Xinghua Avenue (Band Two), Daxing, 102600 Beijing, China; E-mails: email@example.com; firstname.lastname@example.org
Liquid absorption dynamics of packaging papers has been studied with an Emtec PDA device, using water-based flexographic ink and water as testing liquids. While the liquid is penetrating into the paper structure, the measured ultrasonic transmittance values change with the absorption time and form two time regimes. The transmittance increases with time in the first regime and decreases in the second. All of the papers are internally sized and other paper making parameters, e.g., refining and calendering have strong impacts on the absorption behaviour of the papers – for instance, on the maximum transmittance and the transition time from regime 1 to regime 2 – while different fibre blends exhibit only marginal effects. Comparative studies with cloth made of synthesised fibres suggest that it is modifications of wood fibres by the liquids that are responsible for the two-regime structure. Responding to liquid absorption, wood fibres expand in length and width, regain their lumens and change in surface energy, etc. These are probably the origins of the decreasing transmittance in the second time regime.
Keywords: liquid absorption, ink-paper interaction, inkjet, package printing
JPMTR 052 ⎮ 1429 Case study
Novel services for publishing sector through co-creation with users
Aino Mensonen, Katri Grenman, Anu Seisto, Kaisa Vehmas
VTT Technical Research Centre of Finland, P. O. Box 1000, FIN-02044 VTT, Espoo, Finland; E-mails: email@example.com; firstname.lastname@example.org; email@example.com; firstname.lastname@example.org
The traditional goods dominant logic is very much provider-centric. In the case of publishers, journalists produce content for a product such as a newspaper. The product is delivered to consumers, who experience a newspaper service by reading the product. The service dominant logic shifts the focus from provider-centric to customer-centric. Hence, companies need to focus on gathering and sustaining audiences, and on developing their services not just for their readers but together with them. In this study, we present three case studies in which the publishers wish to understand their readers′ expectations and needs regarding new news services and to develop the services together with the readers. Two of the case studies show how to involve the users from the very beginning of the development process all the way to the prototyping. The Owela co-development platform was utilized in all cases.
The study shows the importance of co-creation with users when developing new services. The loyalty and commitment to the publisher′s brand increases when the readers feel that their opinions are valued. The process increases the publisher′s understanding of readers′ expectations and needs and thus emphasizes the users′ voice in the new service under development. Although the cases focus on publishers′ digital news services, the same approach may be utilized in the development of physical products as well.
Keywords: co-creation, digital services, newspaper publisher