Flexo Printing

Definition of flexo printing

Flexo printing is a direct a high-pressure process in which the colour-bearing and non-colour-bearing surfaces of the flexible printing plate are at different heights. The raised areas are image-bearing. Flexo printing is a very easy printing process that can be used everywhere and is primarily used for printing on packaging. This means that the widest range of materials for primary and secondary packaging can be printed in very limited or up to extensive print runs. Food-safety compliant water-based colours are used to print on paper.

Overview of flexo print technologies

A wide range of machine technologies have been developed for flexo printing. In general a differentiation is made between preprint and postprint.

Preprint
In preprint (corrugated cardboard preprint) the paper outside cover of the corrugated cardboard is printed first and then laminated onto the flute with the internal web. This is referred to as web press.

• Flexo central cylinder technology: This is the state-of-the-art web-fed process. The central cylinder printing machine prints with the assistance of sleeves on which the printing plates are mounted. In continuous print lengths of up to 2.06 metres, print images can be implemented at high speed with extreme precision and low waste paper levels.
• Flexo-belt technology: This is an innovative web-fed process that has been specifically developed and patented for the requirements of corrugated cardboard production. The particularly large print formats up to 4.5 metres can largely be produced in one piece and with optimised costs. The printing plates are mounted on endless belts.

Postprint
Postprint (corrugated cardboard direct printing) is a form of flexo printing which prints directly onto corrugated cardboard.

• Flexo-Postprint is suitable for simple print images where high quality is not a requirement. This can lead to what is known as the “washboard effect” which is created through the flutes of the cardboard during printing.
• Flexo-High Quality Postprint (HQPP) is a further technological development of simple direct printing. This is flexo direct printing which is ideally suited for smaller print runs of high-quality printing results and cost-effective production.

Typical uses & benefits of flexo printing

Flexo printing is used nearly all areas of packaging printing. Very good printing results are achieved with printing on paper and corrugated cardboard. Flexo printing is particularly well-suited for solid colours and patterned displays. State-of-the-art technologies in pre-press, printing plate production and machine technology are used to reproduce images with maximum print quality using flexo printing. This printing process is also used to print special colours on elastic and stretchable films, fleece and cellulose, various plastics and aluminium. In the premium segment the quality of gravure and offset printing is almost achieved.