Summary

Newspaper presses are not usually used 24 hours a day. It would be of advantage to the newspaper printer to use his presses mostly during the day to print higher-value products. To achieve this, the print quality would have to come closer to magazine printing. There are two ways of achieving this result: the first way is to mount dryers on newspaper presses and the second way is to use better paper grades. The use of dryers for newspaper presses is a possible option to improve print quality. When a dryer has to be installed on an existing press, there are two main problems: it is expensive and it is sometimes difficult to fit a dryer into existing installations. Another question remains unsolved: what is the achievable print quality on a newspaper press fitted with a dryer using standard newsprint or even better paper grades? It was decided to start a research project on how to improve print quality on newspaper presses. The aim was not so much to try to improve the quality of the daily newspaper but more to look at the achievable quality when dryers and better paper grades are used. This project has been carried out as a commission of IFRA at the Sachsische Institut fur die Druckindustrie (SID) in Leipzig. As this Institute had a press equipped with an electron-beam dryer, a closer study has been made of this possible option for the future. The first part of this report is a feasibility study concerning the use of dryers for newspaper printing. Technological and economic aspects are discussed for hot air, infra-red, ultra-violet and electron-beam drying. The second part gives results of printing tests with different dryers (coldset compared with electron-beam drying and infra-red drying) and different paper grades (standard newsprint. heatset recycled paper. modified newsprint, MFC coldset offset paper and MFC heatset offset paper). We do hope that this work will help our members to have a better overview on the existing possibilities to improve print quality on newspaper presses.