Flexographic printing is a printing method that uses a plate made of elastic material (rubber, resin). The flexographic printing press can be applied for medium and long run printing. Flexography is currently the most popular of all web-powered technologies that have been implemented throughout the printing industry. The main raw material is flexible photopolymer printing plates, this plate has elastic and flexible characteristics, which has the ability to create a fine print image on various substrates, including cardboard, fabric, paper and plastics. The printing plates are made of flexible polymeric material and are strong enough to withstand millions of prints. The process can be roll-to-roll or roll-to-sheet, and is capable of producing speeds of over 150 meters per minute, using UV-cured inks and with a wide range of optional inline operations and embellishments available. In the flexographic printing industry the cliche is also known as cliche, rubber or flexographic plate, all these denominations are valid and are used without distinction. Now, they tend to confuse Clisé with Photopolymer and there we do fall into a naming error, since they are two totally different products and have very specific differences: The Photopolymer: 1.- It is the primary state of the board. 2.- It is not flexible. 3.- It has a film attached. 4.- Its surface is smooth and embossed. 5.- It is not used for printing. The Clisé: 1.- It is the result of the transformation of the photopolymer. 2.- It is flexible and adaptable to any plate roller. 3.- It has relief. 4.- It can be used to print. All flexographic printing machines, whether with a central, conventional or line drum, have a piece called the plate holder roller, where the plate is placed to be inserted inside the printing machine. Once there, it comes into contact with the anilox, which has very small cavities, where the ink is housed and that when rotating rubs against the areas that are in relief of the cliche and while it is rotating the substrate is inked and the image is adhered to said surface. To guarantee a quality print, before placing the cliche it is important to verify certain aspects: 1.- Check the flexographic plates, to detect that they do not have external dirt or any damage. 2.- Verify that the size is adequate, to avoid having to disassemble the cliche and stop production. 3.- Select the mounting tape, which will be used in the printing process and later adhere carefully, since a bad selection will cause the colors not to be correctly registered in the printing run. 4.- Clean the anilox to be used. If the plates are stored correctly, they can be reused several times, here are some recommendations to extend the useful life of the plate: - Keep it in a place where it will not be exposed to external agents that can rub, bend or damage them. - Clean them as soon as they finish printing. - Use the right solvents to remove the ink that is left on the surface at the end of a printing process. Following these steps will provide the printer not only quality prints, but durability of the plate and the printing machine. PLATES or PHOTOPOLYMER PLATES In the market we can mention the brands: Dupont and Macdermid They were originally made of rubber. They are currently made from photopolymeric materials and are generally exposed using "computer to plate" CTP technology. The world of flexographic printing exists a great variety of thicknesses, and that the type of thickness to be used is determined by the type of printing machine and the type of substrate that is going to be printed. Taking this into account, the most commonly used thicknesses in flexographic printing are: 0.45 / 0.67 mm thickness: This thickness is the most used in printers that are dedicated to printing self-adhesive labels for glass or plastic bottles, as well as for printing napkins or paper covers, plastic type film, among others. Thickness 0.100 mm: This thickness is the second most used, and it is precisely because of the great variety of jobs that can be done with it, that is why it is preferred by printers that are dedicated to printing plastic sleeves, as well as in companies that are dedicated to the printing of plastic food packaging. Thickness 0.112 / 0.155 / 0.197 mm: These thicknesses are used by printers of smooth or corrugated cardboard boxes. Due to its versatility, adaptability and high production volume, flexographic printing is positioned as the most used by printers.
