Flexographic printing is a worldwide printing process used to print personalized labels at high speed. It is a traditional printing process that has been perfected over the years. Thanks to a series of advancements in prepress and printing techniques. Flexographic printing is present in various markets and is now the most widely used printing system in the packaging sector for materials as diverse as flexible packaging, corrugated board, paper, compact board and cardboard, sleeves, films, etc. Due to its advantages and characteristics, it has experienced significant growth in the production of labels. This is not intended to be an overly technical article, there are reference books for that, but it will attempt to clarify basic questions about a printing system that it is said the secret of its good implementation lies in the control of variables, due to the large number of processes and materials involved in its elaboration.

What is flexographic printing?

Flexographic printing is a direct printing process (the iron transfers the ink directly to the printing substrate), using mainly rotary printing processes (rollers and material spools of different sizes). The word flexographic printing is derived from the Latin word "flexus", which means curved. This technique is a quick and inexpensive way to apply simple motifs. In addition, colored areas can be applied to a variety of materials such as corrugated cardboard, plastic, self-adhesive labels, envelopes, etc. The main advantage of flexographic printing is the ability to print on a variety of substrates. Flexible plates are used in this technique. They are also called clichés, which for high quality are made of photopolymer, a very durable material that allows more detailed designs. Rubber or caoutchouc plates are also used to make the classic pads, for example. The water-based inks currently used in flexographic printing dry quickly by evaporation and are safe for all types of coatings that come into direct contact with the product. Other inks such as UV (ultraviolet) inks polymerized with lamps are also approved for many products, but low-migration inks are required for food products. Currently, UV LED inks are used to reduce energy consumption and avoid ozone emissions. We also offer this type of machines. .UV printer in pakistan

History of flexo printing

The history of flexographic printing dates back to 1890, when the first printing press was patented in Liverpool and used water-based ink that could easily bleed. In the early 19th century, more pens were developed with rubber plates and aniline oil-based ink. As a result, this printing process is known as "aniline printing" (a term used until the 1950s). At this time, the aniline roller was developed, an ink roller that was engraved and suitable for transferring ink to an aniline printing plate. This roller is still used in flexographic presses today. Over the years, it was discovered that aniline ink was unsuitable for food packaging and was classified as toxic by the Food and Drug Administration. As a result, people began to look for alternatives until the Food and Drug Administration approved new printing inks that were safe for human health in 1949. However, the public continued to be concerned about their health, even though they did not use aniline. In 1951, it was decided to hold a contest to change the name of this process, and in 1952, the name was finally changed to flexographic printing for the good of the industry. Since then, the flexographic printing industry has seen numerous innovations. At the end of the 20th century, flexographic printing was also used in newspaper printing thanks to its simplicity and ease. Today, more than 60% of packaging is produced using the flexographic printing process. Flexographic printing process

First phase: Prepress

Flexographic printing production starts with an idea or a design, usually of a package (boxes, labels, containers, bottles, etc.). This process begins with the creation of the design digitally and ends with the preparation of the printing plates, which can either be done in-house or ordered from an external engraver. Finally, one plate is processed for each base color, which are later superimposed in the printing process to achieve a faithful reproduction of the design. When the plates are ready, they must be installed in a printing cylinder, which is taped. The iron is placed on top of it.

Second phase: Printing

For this we need a flexo printing machine suitable for the type of product to be printed. A machine for label printing (usually inline, coil-to-coil and narrow web) is not the same as a machine for corrugated (usually large format and coil-to-sheet) or for flexible materials (usually central drum and wide web), as examples. Once the plates and the whole press are ready, the second process follows when the formed plate is placed on the cylinder or plate holder roller that is inserted into the press. Inside, it comes into contact with the anilox roller, which can be made of ceramic or steel. Inside the anilox roller are small cavities (cells) that house the ink, which comes into direct contact with the raised areas of the printing plate as it rotates. After inking, the anilox roller continues to rotate until it finally comes into contact with the substrate and creates the impression by transferring the ink to the final substrate. Although flexographic printing, like any other printing process, has its limitations, today it competes with other printing systems for a number of reasons. It also competes with gravure printing because the machines are getting faster, the quality is better, and it is more economically viable for short runs, which is the market trend. It competes with digital printing on cost, except for very short runs. Likewise, it competes with offset printing for long runs in the narrow web sector, which is why the quality, although not up to the highest standards, is beginning to be excellent. In addition, flexographic printing has the advantage of being able to apply large quantities of ink with a much appreciated effect, and it is an indispensable part of combination or finishing machines to apply varnishes, blanks, adhesives, and so on. Technically, we can accept that it has small disadvantages, such as the squash effect, ie. a splash of ink around the printed dot that affects intonation and color matching, the fact that plates deform over time, and that the four-color printing system has its limitations; that marbling occurs (areas that should be printed are not printed due to dirt on the plate), although this can be avoided by having a clean printing plate, or that due to the type of plates and printing system used, dot gain is greater, making fonts and minimum sizes of fonts or lines less precise than with other printing methods. However, registration has greatly improved, even though jobs must be trapped,

Characteristics of flexographic printing

Versatility

Different types of inks can be used in this system. For example, water-based ink, solvent-based ink, or UV-curable ink. In addition, any flexible material can be used, whether porous or not.

Speed

Flexo presses can reach high speeds per minute. This allows for long print runs. Short runs can also be produced at an affordable price.

Automation

A flexo press is very easy to program.

Low maintenance

Flexo printing does not require a lot of maintenance. This lowers the cost of maintenance.

Low cost

The materials used in this type of machine are usually very cheap compared to other printing methods. Although the iron is more expensive, it is a very profitable option that provides a quick return on investment. Environmentally friendly The machines allow the use of recycled water-based inks. The printing plates are also washable with water, making this type of printing more environmentally friendly than others.

Color palette

Simple flexo printing uses 4 colors (CMYK): Cyan, Magenta, Yellow and Black. However, you can use as many spot colors as the particular machine configuration allows to expand the color palette. This way we can print anything we want. Flexo presses

Nil Peter FA-Line label printer

The FA-Line is the most versatile flexo press on the market. Designed to meet the growing demands of the industry, it features an intuitive user interface and fully mobile print controls. With this equipment, performance can be enhanced. With the ability to add additional units, application packages and automation depending on application needs and budget. Its technical specifications: Nil Peter FB-Line label printer. The FB-Line is the answer to the growing need for process automation and greater ease of use.