Optical Brightening Agents ( OBAs ) have been well known for more than a century and have been used for almost 50 years to produce whiter paper. Nowadays, the paper market demands higher Whiteness levels and OBAs are the only way to reach them. The evolution of Ink-Jet technology forces papermakers to balance the demand for Whiteness with printing needs. Until now, it has not been possible to produce a high white paper with excellent printability. Cationic OBAs have been developed specifically for ink-jet applications and have proved to give different benefits to the whole process. Another important issue is the fading process that naturally occurs in any kind of paper and it is even more important within the coated grades. This process could be considerably decreased by understanding its mechanism and by choosing carefully each ingredient of the coating formulation. Practical recommendations are offered to maximise the lightfastness of papers. The aim of this paper is to show the benefits of careful OBA selection for particular paper grades: 1. High White Coated paper 2. High White Ink-Jet paper 3. Coated paper with high lightfastness.
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