PURPOSE: To obtain a system for curing a photosensitive coating on a moving substrate by connecting a temp. measuring device with a computor and a refrigerating device and setting and controlling temp. of cooling water circulating through a reflector-block within a required range.

CONSTITUTION: A system 60 has an intermediate pressure blowers 61 and 62 connected in series, a heat exchanger 70, a refrigerating device 80 and a computor controlling device 90 and air passes through an air feeding pipe 63 and an air filter 64 and is fed into the blower 61 and the temp. is a little raised by being compressed before it is fed to the blower 62 and the temp. is raised again by being compressed furthermore by means of the blower 62. Then, it is cooled through 3 pipe 66 of the first face of a shelf pipe type heat exchanger 70. Thereafter, it passes through a cooled air jetting pipe 67 and flows into an air feeding pipe 47 and an air conduit 42 of each assembly and it passes through an outlet 43 and a reflector-block channel 40 and is evacuated on a lamp 21 or the surroundings thereof to cool uniformly the lamp and to keep the temp. within operational range. As the result, uniform and enough cooling and miniaturization of an ultraviolet lamp reflector assembly is brought about.