Empirical Study of Blade Coating at 2250 M/Min, 1995 Coating Conference Proceedings

Jan-Erik Teirfolk & Jan-Erik Teirfolk Vaito Laaja --The key to increased production capacity of paper coating is to increase the coater speed rather than machine width. This study was undertaken to evaluate the runnability of a blade coater at speeds up to 2250 m/min, to search for limiting factors and to get a first impression of the quality of the paper produced at such high speeds. The production of both wood-free and wood-containing coated paper at two levels of gloss was simulated on a pilot coater capable of speeds > 2200 m/min. The dominant factor influencing paper properties and print results when coating at 2250 m/min compared to 1250 m/min is the corresponding decrease in drying time. The visual ranking was in favor of the papers coated at the higher speed. If done on-line the finishing stage is the limiting factor for producing papers with high gloss at high speeds. The study reveals an interesting challenge, the possibility to produce a better quality coated paper more economically by increasing coater speeds to above 2000 m/min.