Impression cylinder

A printing blanket with a specially manufactured layer designed to give or compress, under pressure from the printing plate and impression cylinder. Compressible blankets resist smashing and usually print a sharper halftone dot. 

In presswork - a sheet of rubber used on a press platen or impression cylinder to cushion the impression in printing. 

In lithography - a rubber coated fabric mounted on a cylinder that receives the inked impression from the plate and transfers (offsets) it to the paper. Such blankets are also mounted on the impression cylinders of sheeted gravure presses. 

Impression cylinder FIGURE 7.6 Offset letterpress (dry offset). 

Impression cylinder—the cylinder which applies pressure to the item being printed, thus assisting the transfer of the print from either the plate cylinder or an offset cylinder. 

The printing plate is laid on a flat bed or forme which passes backwards then forwards (reciprocating bed principle) (see Figure 16.3). At one end of its travel it is inked by rollers and then as it returns the printed item is passed between an upper impression cylinder and the plate. The impression cylinder then rises to allow the forme to return for inking. Due to the reciprocating action, speeds are relatively low, say 3,000 sheets per hour. 

Four colour process with common impression cylinder (4 in Figure 16.6) gives excellent registration with extensible materials. Now a relatively high-quality process. Printing plates are relatively inexpensive—around 175. 

Impression cylinder n. The cylinder on a printing press that holds the material being printed against the printing plate, cylinder, or blanket. 

Rotary press n. High-speed press which passes continuously ruiming webs of paper between an impression cylinder and the curved form on the plate cylinder. 

Once the plate Is dampened and inked, the ink is impressed on the substrate as it is conveyed between the blanket and Impression cylinder. This printing configuration can be contained within a single printing station. Other configurations can involve the use of multiple plate and blanket cylinders which share a common impression cylinder, or where no impression cylinder is used and two blanket cylinders impress images on both sides of the substrate simultaneously as the substrate is conveyed between them. 

An impression cylinder (smooth and polished chrome). A smooth polished chrome cylinder that holds the substrate in contact with the printing plate. 

An impression cylinder. The impression cylinder is a rubber coated cylinder that keeps the substrate in contact with the print cylinder. Its function is to control ink transfer. The ink is drawn out of the cells of the print cyhnder by means of impression pressure and capillary action. An ESA (electrostatic assist) mechanism is sometimes used to assist in the capillary action. Ink rheology, electron charge and surface energy are key variables that effect transfer. 

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