Flexography is a rotary printing process that uses flexible photopolymer plates mounted on rotating cylinders. It is an advanced technology particularly suited for printing on synthetic, woven and slightly irregular surfaces, such as those of technical webbings.
Main advantages:
- Perfect compatibility with the substrate: adaptation to irregular surfaces
Webbing does not have a smooth and uniform surface like paper, but a woven structure characterized by ridges and depressions typical of textile interlacing.
The key element is the flexible flexographic printing plate. Unlike rigid printing systems, which transfer ink only onto the highest points of the weave, the flexographic plate is able to conform to the webbing surface, penetrating into its structure. This allows uniform and complete ink transfer, ensuring continuous, solid and well-defined printing.
- Inline integration: continuity of the production process
To achieve maximum production efficiency, printing must be integrated directly into the continuous process. The webbing is woven, printed immediately, and then fed into cutting and sewing operations without interruptions. Printing must therefore not become a bottleneck.
Flexographic machines are designed to operate at high speeds. The rotary roll-to-roll principle makes them ideal for continuously unwound materials such as webbings. The use of fast-drying inks, often instantly cured using UV technology, allows printing speeds perfectly aligned with the productivity of industrial looms. Slower processes would require additional winding, handling and unwinding stages, resulting in increased time, costs and labor.
- High print durability: long-term performance
Printing on lifting slings or ratchet straps must withstand severe operating conditions, such as repeated bending, abrasion from contact with loads or metal components, exposure to UV radiation and, in some cases, moisture or chemical agents. Under these conditions, conventional inks would be inadequate.
Flexography uses inks specifically formulated to ensure high adhesion to synthetic fibers such as polyester and nylon. Ink anchoring: these inks are designed to create a chemical bond with the substrate, ensuring superior adhesion compared to simple surface deposition. UV-curable inks: UV technology represents a decisive advantage. After application, the ink is immediately cured by high-intensity ultraviolet lamps, forming a compact and resistant layer with excellent resistance to abrasion, chemical agents and fading.
- Economic efficiency for long runs: industrial-scale production
Webbings are generally produced in large volumes, often thousands of meters with the same logo or repeated text. It is therefore essential to adopt a printing solution that is economically efficient on a large scale.
The printing cost per meter is extremely low. High production speed and reduced waste make flexography the most efficient technology for the long, repetitive runs typical of webbing manufacturing.
The inline process
To fully understand the effectiveness of this approach, it is useful to consider the production sequence:
- Weaving: an industrial loom produces thousands of meters of polyester yarn, forming a continuous roll of flat webbing.
- Inline printing: the webbing, without stops or intermediate storage, is fed directly from the loom into the flexographic machine, where the rotating cylinder with the customized plate continuously prints logos or text at predefined intervals.
- Curing: immediately after printing, the webbing passes under a UV lamp that instantly cures the ink, bonding it to the fibers.
- Finishing: the printed and fully cured webbing continues along the line for hot cutting to the required lengths and for subsequent packaging and sewing operations.
Flexography ensures an optimal balance between print quality on complex surfaces, high-speed in-line integration, long-term durability in demanding working environments and economic efficiency for mass production. For these reasons, it represents the reference solution for high-volume customized webbing applications.
Written by Marcello R. | Sales Department, Giugni®
