Of all the processes that currently exist for label printing, flexographic printing is undoubtedly the preferred one by all.
The speed, image quality and the high volumes of copies that can be obtained in a very short time, are some of the many advantages that this type of printing has. Now, what is the process for its elaboration? What considerations should we take into account? We will show you in a simple way how to take a label from paper to reality.
Define the art and the colors to be used, for this it is important to take into account which printing machine will be used, to define what color capacity can be printed on it. On the market there are machines with a capacity from 1 color to 8 colors. For example, this art has 4 colors in its design:
An important part in the design is to know the dimensions of the label, because this determines the type of roller and other technical information, where the cliche will be placed.
Having the previous point clear, it is necessary to adapt the art to the size of the flexo plate roller of the printing machine, since there are many sizes.
The roller also determines the following information:
- The Rows: which are the columns that the design will have on the circumference of the roller.
- Repetitions: refers to the number of times the design will be repeated on the circumference of the roller.
- Lineatura: it will depend on the type of machine and if the image has patterns or flat colors
- Photopolymer thickness: it is the thickness of the sheet where the design will be exposed to obtain the cliche.
Once the Prepress Design area has all the technical information, a model called ´´Mounting´´ is elaborated, where they show the printer how the cliche will be engraved, verifying and comparing the design, with the roller and the machine what to use.
Manufacture of the Photopolymer
At this point, the prepress design area proceeds to separate the colors of the art, to expose the photopolymer plates to the transformation process, so as many cliches will be manufactured, as the colors have the design. For example, if the art has 4 colors, each color would be a photopolymer plate, which will later make up the label that will be printed.
Once the plates have been obtained, they are placed on the plate holder rollers of the printing machine, in the color that corresponds to each one, so that as the material (label) passes through each color ink station, it is impregnated with pigment and This is leaving the final design engraved.
Most common mistakes when creating a label:
1.- The colors of the design do not correspond to the color capacity of the printing machine.
2.- The dimension of the design does not agree with the size of the roller and therefore everything else.
3.- Lack of technical information between the printer and Prepress.
4.- Very small texts, which later cannot be distinguished in the print, causing them to appear stains at sight.
5.- Very thin elements or lines, since they run the risk of being lost when making the cliche or making the impression.
Close communication between the prepress and the printer is vital to obtaining high-quality prints on labels.