In the last years the Swift mission monitoring of non-GRB sources has become an essential tool in multi-frequencies time- domain studies. The ASI Science Data Center (ASDC), which hosts one of the three official Swift data archives and was deputy for the X-ray Telescope (XRT) Deep and Serendipitous surveys, has a long experience on Blazar multi-wavelength campaigns and has recently participated to various campaigns contemporary to observations of new space missions, such as Planck and NuSTAR (Balokovic et al 2016, Furniss et al. 2015, Giommi et al 2012). Since 2006 at the ASDC we have started an activity of UltraViolet Optical Telescope (UVOT) Blazar image processing. The dedicated standard processing procedure of UVOT images, using official software and calibrations, has the goal to add UVOT fluxes to source Spectral Energy Distributions (SEDs) and also support variability studies with comparison to X and gamma-ray data, even on the intra-observation time-scale. Currently data of about 430 sources have been processed, and results have been used in recent papers, such as those on Mkn 421 (Balokovic et al.2016) and OJ 287. The OJ287 UVOT image complete data processing is updated at each observation campaign and results have been published in some survey papers. The 2015 observations have been included in the internal long-term monitoring of the source and considered in the recent multi-frequency study Valtonen et al.(2016) of the new optical-UV outburst of the 12 years cycle, with comparison to the ground optical data and the contemporaneous Swift X-ray ones. We will report the results obtained with UVOT data.