Reshaping Coated Paper Production in N.A. With Film Coating, 2005 TAPPI Coating Conference

For several decades, coated paper grades have been produced in North America in different ways by using primarily blade coating technology, either on-line or off-line. However, for some years now more and more film coaters are being considered on machine upgrades, either as pre-coater for double coated grades or as the only coater for single coated grades. This is true for wood-containing grades as well as for wood-free coated grades. Some new grades have even been created which could be placed in between well-known grades. One of the driving forces for this reaction from the paper makers is based on the necessity of differentiate from common grades been produced at higher costs. At the end, competitiveness is surely the main reason for trying to produce coated grades more efficiently at lower cost, and be able to compete in the N.A. paper market. The World financial markets also induce the necessity of being more creative and innovative – volatile exchange rates, large prices increase in steel and petroleum base products, etc. And in order to achieve those targets, film coating technology is definitely one of the important tools available to assist on this task.

The different coated paper grades that can be produced using film coating technology, and in some cases already being produced in N.A., will be discussed in this paper. Film coaters have been and are still the preferred alternative along with modern on-line calendering technology for machine upgrades, reshaping the way coated papers are produced. The classic machine configurations with on-line blade coaters with soft calenders as well as off-machine coaters and off-line super calenders are being replaced by on-line film coaters with multi-nip calenders because of higher productivity and lower installation costs.

A new potential utilization of film coaters as a the only coater to produce double coated grades will be detailed discussed in this paper. Pilot trials were performed by utilizing film coaters twice in the coating process, in particular, for wood-containing coated grades (Medium Weight Coated – MWC range) without the use of conventional blade coating technology. Pilot Trial results are going to be presented, including calendering as well as printing trials, demonstrating the potential of this new use of such technology for double coated paper production.