What is Flexographic Printing?
Flexographic printing is a printing method that can be applied to various materials, such as plastic, paper, cardboard, and more.
As the name suggests, flexo printing uses flexible printing plates. The term “flexo” is derived from the Latin word “Flexus,” meaning flexible.
Flexographic printing is actually a modern version of letterpress printing (which uses raised metal letters and images for printing). However, flexo printing has surpassed letterpress, allowing printing on materials like plastic films, metal foils, cellophane, cardboard, and paper in a consistent and uniform manner.
History of Flexography
The first printing machine was invented in Liverpool, England, in 1890 by a person named Bibby. By 1900, this machine was used more professionally in European printing houses with rubber plates and ink based on petroleum aniline, which became known as aniline printing. Over time, printing methods advanced, and names were chosen for each method. The name flexography emerged as the most popular among three contenders: Permatone, Rotopake, and Flexographic, and it was officially adopted. In 1980, flexography began to be used as a method for printing plastic stamps.
How Does Flexographic Printing Work?
Flexographic printing is done directly and under high pressure with flexible photopolymer plates. Direct printing means that a gelatin plate, which is coated with ink, comes into direct contact with the substrate to transfer the image onto it.
This printing method is layer-based and is cost-effective for large projects. It allows for printing on all layers, making it suitable for various applications.
Flexography can print on virtually all products, and it is commonly used for printing on plastic or cellophane packaging.
What Are the Differences Between Flexo and Offset Printing?
The plates and layers used in flexo and offset printing are different. In flexo, flexible plates are used, whereas offset printing relies on a flat surface. In offset printing, the inked image is not transferred directly to the substrate, but in flexo, the inked image is directly transferred onto the substrate.
What Are the Differences Between Flexo and Gravure Printing?
Flexographic and gravure printing differ in terms of plate material and printable surface. Gravure plates are made of metal and have a longer lifespan compared to flexo plates, which are made of photopolymer or rubber.
Advantages of Flexographic Printing
- The printing speed of flexo is much higher compared to other printing methods.
- It can print on a wide range of materials.
- It is very cost-effective for large print runs.
- The layer-based process ensures continuous printing for large projects.
- It uses a variety of color palettes (usually cyan, magenta, yellow, and black), referred to as four-color flexo printing.
- All printing, laminating, and die-cutting operations are completed in a single pass.
Products Printed Using Flexography
Many products around us are packaged using flexographic printing. These products include:
- Food and beverage packaging
- Packaging for envelopes, newspapers, magazines, and wallpaper printing
- Packaging for liquids such as fruit juices, mineral water, and sodas
- Carton printing
- Printing on paper or plastic shopping bags
- Wallpaper printing
- Printing on Naylon bags
- Printing on office forms
- Shrink film printing
- Corrugated cardboard
- Metal surfaces
- Fabrics
Types of Flexographic Printing Machines
What kind of machine is used for flexographic printing?
Flexographic printing is mostly done with roll-to-roll printing machines, but some applications use sheet-fed machines. These machines are categorized based on the arrangement of the printing units, which are:
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Column-Type Machines
In these machines, the printing units are arranged vertically relative to each other, and each unit has its own pressure setting.
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Horizontal-Type Machines
In these machines, the printing units are separate and placed horizontally in a sequence.
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Central Impression Cylinder Machines
These machines differ from the two types mentioned above, as the printing units are independent and arranged around a central impression cylinder. The components of these machines include unwinders, printing units, dryers, and rewinders.