A container treatment machine for printing on containers, including a transport unit optionally configured as a carousel and used for conveying the containers in circulating container reception apparatus, at least one direct printing head for printing with a light-curing printing ink, and a stationary curing unit for curing the printing ink on the containers by light radiation, optionally UV light radiation, characterized in that each of the container reception apparatuses is provided with a shielding enclosure used for shielding off light radiation and having at least one access opening for the curing unit, and the curing unit is provided with a shielding element cooperating with the access opening of at least one shielding enclosure such that direct exit of light is prevented.