Experimental papers with varying alkylketene dimer load were prepared and characterized with respect to size retention, reaction and hydrolysis. The characterization was done by using extraction studies, in combination with X-ray photoelectron spectroscopy and gas chromatography. The surface energy of the produced papers was evaluated using the Good-Oss method. It was shown that by stepping up size additions, both the polar and van der Waals components of the surface energy are reduced.