Characteristics of Flexo Printing and Flexographic Presses

· Relief printing is a direct printing process. Relief printing plates include metal type plates, copper and zinc relief plates, duplicate relief plates, photopolymer relief plates, electronically engraved relief plates, and flexographic plates.

· Flexographic printing is a printing process that uses flexible printing plates and transfers ink through an anilox roller.

· Flexographic printing combines characteristics of relief, offset, and gravure printing:

o The image and text areas of a flexographic plate are raised above the non-image areas, giving it the characteristics of relief printing.

o The flexographic plate is highly elastic, similar to the blanket in offset printing, giving it certain characteristics of offset printing.

o The use of an anilox roller for ink transfer is similar to the ink-transfer principle of gravure printing. Its structure is relatively simple, giving it characteristics of gravure printing.

· Flexographic printing offers a short plate-making cycle and relatively simple plate-making equipment. It can print on a wide range of substrates and provides high printing speeds and production efficiency. Water-based inks with low environmental impact and fast drying can also be used, giving flexographic printing significant environmental advantages.

Classification of Relief Printing Presses

Relief printing presses can be classified according to their mechanical configuration into flat-bed, cylinder-to-flat, and rotary relief printing presses.

1. Flat-Bed Relief Printing Press

Flat-bed presses include:

· Hinged platen presses 

· Swinging-platen presses 

· Parallel-platen presses 

These presses generally have lower printing speeds, lower production efficiency, and smaller printing formats.

2. Cylinder-to-Flat Relief Printing Press

According to the movement of the impression cylinder, cylinder-to-flat relief presses can be divided into:

· Single-revolution presses 

· Two-revolution presses 

· Stop-cylinder presses 

· Reverse-motion presses 

Compared with flat-bed relief presses, cylinder-to-flat presses offer higher production efficiency, larger printing formats, and lower printing pressure.

3. Rotary Relief Printing Press

In rotary relief presses, both the impression mechanism and plate cylinder are cylindrical. According to the paper-feeding method, they can be classified into:

· Sheet-fed rotary relief presses 

· Web-fed rotary relief presses 

Rotary presses operate smoothly and at high printing speeds, making them well suited for double-sided and multicolor printing.