Influence of inertia on liquid absorption into paper coating structures

We elucidate in this paper the influence of inertia of the imbibing liquid with special attention to the printing of paper. This is used to explain the observed differences between the absorption properties of fluids into large and small pores in paper coating structures. Without invoking arbitrary changes of the assumed constants in Lucas-Washburn (Washburn 1921) it has been hitherto impossible to describe the retarded imbibition seen when absorbing into highly porous structures containing large pores, for example in matt papers or coatings derived from very steep particle size distribution pigments.