Paper was preserved by deposition of poly(cyclohexene oxide) polymerised in situ by a photoinitiated cationic process. The efficiency of the deposition, as function of parameters such as the used catalytic system and the reaction time, has been evaluated by detection of uncovered cellulose present at the sample surface determined by means of X-ray photoelectron spectroscopy. The percentage of uncovered cellulose detected was ranging from 1 to 40%.