The thermal paper nowadays in use for labelling food products is subject to degradation processes which make it unreadable after a comparatively short time when submitted to the low temperatures in the refrigerated stocking areas as well as when the products undergo preservation treatments after having been labelled. This has generated a growing demand for coated thermal paper, i.e. resistant to low and high temperatures and preserving agents.
Other applications of coated thermal papers are in the mechanical industry, which needs coated thermal paper to label, by bar code, semi-worked items which have to undergo further treatments which normally involve manipulation and lubrication. All this mechanical stress on the label and contact of the inks with lubricating fats affect the readability of the label.
Leisure industries also need coated thermal paper in particular weather conditions. A typical example of application is the "sky-passes" which must be resistant to low temperatures and frost as well as to manipulations.
The main objective of the proposed research is therefore the development of a new European technology to produce coated thermal paper with innovative recyclable materials mainly for use within the food packaging industry, but also with applications within the other sectors previously described.
results
Within the framework of the RTHP research project many important results were obtained, both in terms of scientific progress and in terms of industrial application possibilities.
The industrial results obtained can be divided into two main categories: those applicable in the short term and those that will need further experimental work to be put into practical industrial use. The results, which are exploitable in the short term can be summarised as follows:
- Alternative formulations for the production of thermal sensitive papers not totally depending from Japanese raw materials.
- Use of natural products in the production of such papers.
- Formulations for the production of both "normal", "semi-protected" and "protected" thermal papers using natural products for coating.
- A comprehensive study of the influence of the new coating materials in the calender process.
- A comprehensive study of the behaviour of the new product for what concerns energy consumption during the thermal reaction.
- Design and laboratory production of a new “echo-paper” apt to be used as support for the production of thermal papers.
- Possibility to use the newly developed products separately in the actual market production.