Current research projects (in the field "print finishing")
Development of a method for assessing the coating strength of printing papers during binding processes
Timescale: 01.03.2016 to 28.02.2018
Programme of the Federal Ministry of Economics and Energy for the support of "Industrielle Gemeinschaftsforschung (IGF)" via the German Federation of Industrial Research Associations (AiF)
Today, the printed book is in competition with digital books (eBooks). In parallel with the declining print runs that are associated with this, the expectations of publishers and readers are increasing with regards to the quality of hard and soft covered books. There are many types of bound products but high quality illustrated books are one of those that are likely to maintain a relatively stable market position. The illustration printing papers used for them are coated multiple times and are selected for the high print quality that it is possible to achieve. Properties that have an impact on how successfully they can be finished are not generally taken into account. In Fogra's experience, there has been a decline in coating strength. Consequently, coating cracks in the fold again and again result in clearly lower quality products. If large areas of the spine glue detaches from the spines of the book blocks then, as a rule, it is no longer even possible to carry out repairs. This means that there is a need for it to possible to test coating strength, a paper quality that has not previously been recorded quantitatively, in a standardized way. The aim of the research project is to develop test methods for assessing coating strength in the fold. As well as focusing
on the detection of coating particles detached from the folded edges, the intactness of the folded edges will also be investigated. In the first instance, laboratory methods will be developed for both test methods that will allow a standardized implementation in terms of measurement accuracy and reproducibility. Practical methods should then be derived from these laboratory methods that, whilst simplified, should exhibit as close a correlation as possible with them. The test method for particle detection is divided into the following sections: folding the sample, picking up the detached coating particles and assessment of the coating cracks. An appropriate folding device and process that is as simple as possible will be developed for the practical method on the basis of the parameters that are found to influence the folding result.
Foundations for the standardization of abrasion tests on printed samples
Timescale: 01.06.2014 to 31.05.2016
Programme of the Federal Ministry of Economics and Energy for the support of “Industrielle Gemeinschaftsforschung (IGF)” via the German Federation of Industrial Research Associations (AiF)
Partner: Papiertechnische Stiftung (PTS), Heidenau
This project should lay the foundations for the revision of an abrasion test standard (ISO 18947), which has been developed by ISO TC 42 (photography) for photobooks and photos produced by digital and analogue means. It consists of two parts, one scientific, the other devoted to standardization. The Papiertechnische Stiftung [Paper Technical Institute] has been secured as a partner, which means that a controlled climate chamber and enhanced analytical equipment are available. The objective of the project is to transfer the standard from the field of digital photography to printed products in general. Besides the “Sutherland” abrasion testing device that is implicitly favoured in ISO 18947, the intention in this project is to also use the prüfbau “Quartant”, the IGT “RT 4” and the James Heal “Martindale” devices to test samples printed by means of various different printing methods with a view to reaching conclusions about the comparability of devices, repeatability and precision. The factors influencing the results of the tests will be investigated for all the devices. Besides developing the methodology, the influences exerted by materials (wax content of inks, stickiness of the dry ink film, proportion of crosslinking binding agent in the ink film, surface topography of the paper and print, surface elasticity of the paper and print and pore volumes of the paper and print) on sheet-fed offset printed samples will also be investigated.