At PRINTINGBROCHURE.NET, we provide you with a clear explanation on the two most important brochure printing systems –conventional offset and digital printing– for you to better understand how they work.
Conventional offset printing, also known as lithography, is the most common way to obtain quality brochures in great quantities and fast. This printing method allows printing on all types of paper. It also allows printing in full colors with the chromatic CMYK system –a combination of cyan, magenta, yellow and black to obtain the rest of the color palette– and with Pantone colors, and the printing of small and large print runs. One of the main advantages of offset printing is the excellent image definition it offers. Apart from this, this method of graphic reproduction allows the printing on different supports: paper, fabric, wood and metal.
This printing system involves some previous steps. Firstly, the design of a brochure –or any other graphic piece– is recorded from a digital file on film negatives by means of a special device known as an imagesetter. Secondly, the design on the film is transferred on a plate, which will show the brochure just as it will look when printed. Then, the images on these plates are transferred to an aluminum plate. This plate, which is placed on a roller, will receive ink and water, and then transfer the design onto a rubber blanket which is also placed on a roller. Brochures that comprise different colors will need different elements –plates and negative films– for each color.
The printing phase that has been described previously consists in the transfer of an image to paper. The offset system works specially by means of water and oil.
The plates with the images are covered with a photochemical compound to treat the areas to be printed. Then the plate is wetted with ink and water. The areas treated with the hydrophobic compound (the image to be printed) absorb the ink. In the areas that were not treated the oily ink is repealed since water and oil don’t mix. The plate transfers the design onto a rubber blanket placed on a roller which will print on the paper. For the printing to be a complete success, the printer should control colors proportions, dot gain precision and paper stillness.
Offset system can work with paper rolls or sheets of paper. Generally big printing presses use paper rolls because they allow the production of high volumes of products in a short period of time, and double-sized printing. Some printing presses using paper rolls may have ink drying systems and some others may not. Those that include this system have a device that dries the ink as paper is rejected from the press. This fastens the printing on any type of paper –including glossy or matte text paper. This type of printing presses is usually used for printing magazines and newspapers because they can print large print runs. When it comes to printing brochures, printing presses with ink drying systems are the best choice. They allow the printing of high quality images. In the case of offset printing presses without ink drying systems, the ink dries thanks to the air in the environment. For this reason, only paper with no finishes can be used. These printing presses don’t offer high quality images. However, they have an advantage over other systems: low costs.
On the other hand, there are printing presses that use sheets of paper instead of rolls. These machines are used to print small volumes of products on different types of paper. They offer high quality printing and this is why they are recommended for printing high definition brochures in small print runs. They are also very slow, which makes them more expensive than roll paper presses.
The digital printing system is a system used today to print small print runs of graphic material. It’s also an offset printing system but, unlike conventional offset printing, it doesn’t use metallic plates or film negatives. This is its main advantage as previous preparations are not needed and time and money are saved as a result. The design of the graphic piece is directly transferred to the printing machine. This is why we call it digital printing –the reproduction of digital images on paper.
This system allows printing on all types of paper, in full color, rapidly and at lower costs than conventional offset systems. This occurs because films and metallic plates are not necessary. Material printed using a digital system presents high quality image definition. Another advantage is that they allow the printing of small print runs –up to 1,000 copies– according to each company’s needs. Offset printing is more convenient for large print runs. Printing in small quantities with a conventional offset system implies big investments since the simple functioning of the offset printing press involves the use of films, plates and labor.
Apart from this, with digital printing, corrections can be made easily thanks to the lack of metallic plates. As a digital system, images are reproduced on each printout and, correct them or customize them is possible. In this way, customized brochures, that is, brochures that are different from one another can be printed. This is not possible with offset printing. Each brochure can be original. As regards colors, unlike conventional offset printing, digital printing allows printing in different colors at once. Digital printing quality is just as good as offset printing, with clear images, defined edges and consistence. Because of the many advantages that digital printing systems offer, this is a good option to print small print runs of brochures.
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