Structural Characteristics of Pore Networks Affecting Print-Through

The pore structure of handsheets and of commercial newsprints is described in detail. The advantages and limitations of scanning electron microscopy and synchrotron radiation X-ray microtomography for pore-structure assessment are discussed This gives insight into the two-dimensional and three-dimensional characteristics Of the pore structure. A major achievement is the effective quantification of the submicron pores by scanning electron microscopy. It is demonstrated that submicron pores contribute positively to light scattering per unit thickness. The relationship between the pore structure, the light scattering and print-through is explored