Abstract: A method of printing a succession of images on to an elongate web, in at least two colors, comprises feeding the web past the first and second rotating printing cylinders 10 and 11, the first print cylinder applying a first color and the second print cylinder applying a second color, and periodically interrupting the movement of the web past the print cylinders, the length of the interruptions controlling the repeat distance, and the interruptions of the movement of the web past the second cylinder being controlled in dependence upon the images being produced by the preceding print cylinder. The web may be driven by means of a servo motor such that the extent to which the web moves while the motor accelerates to and/or decelerates from, its normal running speed is accurately predetermined.

Abstract: In the operative position shown in FIG. 4 a printing roller abuts the cylindrical surface of an impression roller to cause ink to be transferred from an anilox roller via the printing roller to the impression roller. The gear wheel on the impression roller meshes with a gear on the printing roller which in turn meshes with a gear on the anilox roller to cause rotation of those three rollers.The printing roller and the anilox roller can be moved to the right, when viewed in FIG. 4, to move their co-operating cylindrical surfaces out of contact with each other, and yet still leave their gears in mesh in order to enable the printing roller to be changed and yet maintain the rotation of the anilox roller. A clutch is provided to enable the printing roller to be stationary when being changed, or to enable the printing roller to be correctly aligned with the impression roller when brought back into co-operation therewith.