The 12th China Academic Conference on Printing and Packaging

I have a subscription to the Journal of Imaging Science & Technology (JIST). JIST has recently featured articles from the 12th China Academic Conference on Printing and Packaging that took place in Beijing in November 2021. The aim of this article is to review the papers that I believe are relevant to the readership of Authentication & Brand News™ (ABN) and to illustrate the value of such journals to our community.

As with most wide-ranging conferences the papers can be categorised into those with direct relevance, those that give useful insights and those that provide a flavour of current research in the field, in this case within the Chinese academic community. This review will deal with these in that order.

Chunghui Kuo, editor-in-chief of JIST, notes in his editorial that research on printing technologies has become increasingly multidisciplinary, requiring wide ranging collaborations across research fields.

These papers provide an example of these and the potential for these to add to the technologies of authentication and brand protection.

Papers of direct relevance

A paper from Hunan University of Technology describes a reversible thermochromic ink with security print applications in mind. This is an active field as these compounds find use in other larger applications such as temperature indicators, wearable electronics and medical diagnostics.

The authors prepared a crystal violet lactone as the coloured compound that decolorised around 50°C and formulated it for offset printing. It is interesting to note that this work was part funded for ‘the Research and Application of Key Algorithm for Intelligent Inspection of Goods Packaging on Shelves’.

A collaboration between Jingchu University of Technology and Wuhan University has resulted in the synthesis of fluorescent carbon quantum dots from sustainable plant-based material. As a result, unlike some other quantum dot technologies, there is no toxic element content. They formulated the quantum dots into both an inkjet and fountain pen inks to demonstrate capability and fluorescence under 365nm (UV) illumination. Peak excitation from their formulation was at 335nm, so some optimisation of their process could be useful for secure document applications.

Other papers of relevance

Just because these papers do not specifically reference secure document or brand protection applications does not necessarily make them any less relevant to our community. The value is often in the vision to apply them in our field and to harness their thought processes in our direction. In this spirit I found the following papers interesting from our perspective.

A paper from universities in Qilu, Jinan and Zhengzhou, including the Information Engineering University, presented work on a water-based varnish suitable for inkjet printing onto offset paper. In addition to surface protection, clear ink printing has the capability of providing basic optical features due to their resemblance to traditional paper watermarks.

Work from the Beijing Institute of Graphic Communication examined the characteristics of silver inks applied by gravure printing for printed electronics. This work is interesting as printed electronics has a place within the ABN community, and the paper outlines some of the key performance characteristics to be investigated when applied with a gravure press.

A further paper from this group is significant in that it also comes from their School of Printing & Packaging Engineering. In this case it is again utilising printed electronics, this time to add touch sensor functionality to screen printed devices. It will be interesting to observe how innovations such as these impact brand protection.

Still in Beijing, their University of Chemical Technology presented a paper showing how to increase the resilience of water-based inks for polyethylene and BOPP substrates, a combination of interest to some tax stamp applications. Like many of these papers, it also provides a literature survey to relevant work.

A collaboration between Xi’an University of Technology and Shaanxi Beiren Printing Machinery Co produced a model for roll-to-roll tensioning systems, in this case for gravure printing. Tension control is particularly important in our community as it controls registration between different ink layers.

Some common themes were apparent in these papers. There is significant breadth and depth to the work being done by these groups in China on printing and packaging. In addition, there is strong emphasis placed on design for sustainability and in particular the use of water-based chemistries.

Other work

Further papers from Information Engineering University, Wuhan University and contributions from Henan Universities, Quzhou University and College of Technology, Time Publishing and Media Co and Shanghai Publishing and Printing College added to the list of papers.

Of relevance to ABN readers is some of the ongoing work on colour measurement and perception. This adds to the relevance for us of academic conferences and journals such as JIST.

The value of academic publications The stated objective of JIST is to ‘provide the imaging community documentation on a broad range of imaging research, development, and applications to promote communication and understanding across the boundaries of the many disciplines involved in modern imaging’. They use the term imaging in the broadest sense, publishing papers on input technologies such as camera systems in addition to the output technologies of printing processes.

There is one further journal in this field that is worth bringing to the attention of the ABN community – the Journal of Perceptual Imaging (JPI). This is an open access journal that publishes ‘research at the intersection of perception and imaging’, which covers the visual perception of documents and displays. As much of our work pertains to inspection for authentication, this journal too can bring some valuable insights.

As an example, a paper in January 2022 from Envision Research Institute, Smith- Kettlewell Eye Research Institute and University of Dhaka examined human perception and appreciation of tactile objects by vision and/or touch. Given our use of tactile features such as intaglio printing, this was an interesting study which in summary found that the tactile experience predominates and that characteristics such as smoothness and softness can have significant impact.

All the JIST papers reviewed here appeared in JIST Volume 66 #2 - https://library.imaging.org/jist/articles/66/2.