The distribution of papermaking chemicals on the surface of various uncoated and coated papers was investigated by ToF-SIMS, FE-SEM, EDS, and XPS. Four paper samples, two office papers, one matte-coated and one traditionally coated paperboard were investigated with the aim of evaluation of chemical microscopy methods for examination of morphological and chemical heterogeneities on paper surfaces. Distribution of fillers, pigment particles, size, optical brightener, latex and other paper and coating components was assessed. Application of Au-Pd treatment on paper and coating surfaces prior to ToF-SIMS imaging increased the secondary ion counts for the region of low intensity peaks and improved the chemical mapping of papermaking and coating chemicals. ToF-SIMS imaging is shown to be a valuable and promising technique for chemical microscopy of paper surfaces. (c) 2004 Elsevier B.V. All rights reserved.