Development of New Methods for Characterizing Uniformity of Yankee Coatings

An adhesive coating formed on the surface of a Yankee dryer is critical for manufacturing creped tissue and towel grades. Due to the complexity and dynamic nature of the creping process, there has been very limited information available on the structure of Yankee coatings. This paper discusses laboratory methods for preparing Yankee coating films and imaging techniques, atomic force microscopy (AFM) and scanning electron microscopy (SEM) that were used to characterize these films. The effects of various modifying agents are demonstrated on the structural and compositional uniformity of the Yankee coating films. The applicability of the SEM and AFM data from this study to the actual creping process and the practical aspects of the results are also discussed.