Method and device for high speed printing

A device for printing an impression on a web, said impression having a length equal to a web format, said device comprising:

• a printing transfer cylinder;
• and
• means for imposing an impression of said web to be printed on a course passing in immediate proximity to said printing transfer cylinder, said means for imposing comprising:
• take-up means disposed downstream of said printing transfer cylinder for continuously drawing said web with a predetermined constant take-up speed in one direction,
• two pressure cylinders movable between a withdrawn position and a use position wherein said two pressure cylinders maintain said web in printing contact with said printing transer cylinder at two contact points during a printing phase,
• means for increasing the speed of said web as it contacts said printing transfer cylinder during said printing phase, said speed increasing means forming a slack portion of said web between said take-up means and said transfer cylinder during said printing phase, and
• means for retensioning said slack portion of said web including
• a first rotary vacuum means positioned upstream of said printing cylinder and before said take-up means, means for rotating said first rotary vacuum means in said one direction at a second predetermined speed less than said constant take-up speed of said take-up means.