Reshaping Coated Paper Production in N.A. with Film Coating

摘要

For several decades, coated paper grades have been produced in North America in different ways by using primarilyrnblade coating technology, either on-line or off-line. However, for some years now more and more film coaters arernbeing considered on machine upgrades, either as pre-coater for double coated grades or as the only coater for singlerncoated grades. This is true for wood-containing grades as well as for wood-free coated grades. Some new gradesrnhave even been created which could be placed in between well-known grades. One of the driving forces for thisrnreaction from the paper makers is based on the necessity of differentiate from common grades been produced atrnhigher costs. At the end, competitiveness is surely the main reason for trying to produce coated grades morernefficiently at lower cost, and be able to compete in the N.A. paper market. The World financial markets also inducernthe necessity of being more creative and innovative – volatile exchange rates, large prices increase in steel andrnpetroleum base products, etc. And in order to achieve those targets, film coating technology is definitely one of thernimportant tools available to assist on this task.rnThe different coated paper grades that can be produced using film coating technology, and in some cases alreadyrnbeing produced in N.A., will be discussed in this paper. Film coaters have been and are still the preferred alternativernalong with modern on-line calendering technology for machine upgrades, reshaping the way coated papers arernproduced. The classic machine configurations with on-line blade coaters with soft calenders as well as off-machinerncoaters and off-line super calenders are being replaced by on-line film coaters with multi-nip calenders because ofrnhigher productivity and lower installation costs.rnA new potential utilization of film coaters as a the only coater to produce double coated grades will be detailedrndiscussed in this paper. Pilot trials were performed by utilizing film coaters twice in the coating process, inrnparticular, for wood-containing coated grades (Medium Weight Coated – MWC range) without the use ofrnconventional blade coating technology. Pilot Trial results are going to be presented, including calendering as well asrnprinting trials, demonstrating the potential of this new use of such technology for double coated paper production.