Printing Process
From high pressure to digital printing:
The most important printing techniques at a glance.
Do you know exactly what we are talking about when the term "offset" comes up? Or how our banknotes are printed? And what to print when there were no computers? Digital printing is not that old - and by far not the only possible printing process.
1. High pressure - the oldest printing process in the world.
Most of us came into contact with the principle of high pressure at an early age - for example, at school linoleum printing or when printing potatoes from kindergarten days. The process itself was invented by Johannes Gutenberg: As the founder of modern letterpress printing, he revolutionized the conventional methods of book production around 1450 with his movable metal letters and the printing press.
In high-pressure printing, the parts to be printed are sublime: only what stands high on the printing form - lines, webs or surfaces - is printed. These parts are colored and then pressed directly onto the paper or other material (direct printing process). Therefore, the printed image on the printing form must also be mirrored! The printing forms are either hard (wood or metals) or soft (rubber, linoleum, etc.).
Today, high-pressure is mainly used for sophisticated graphics or elaborately designed book printing. However, high-pressure techniques also include flexographic printing, which today can be used to print on many materials that are unsuitable for other printing processes: for example, plastic packaging, films, napkins, wallpaper or corrugated board.
In high-pressure, a particularly haptic quality can be achieved: Reliefs that are created by the pressure on the paper, are often deliberately used as a design tool, for example, embossed business cards. However, high-pressure is not cheap, the production of the printing plates consuming, and small runs are worthwhile due to the installation costs hardly. Because the printing plates wear over time, too high print runs are also not economical: In the field of everyday print products, therefore, today rely on processes such as digital and offset printing.
2. Flat printing (offset) - for newspapers in millions
In movies often appears the image of giant rotating paper rolls spewing out freshly printed newspapers with the latest headlines: web offset printing - a planographic printing process that is one of the best known and most popular in the printing industry. Caspar Hermann introduced the first of these offset printing machines to the general public at the beginning of the 20th century.
In contrast to high-pressure, planographic printing is an indirect printing process: The ink is not transferred directly from a plate to the material to be printed (eg paper), but first to a roller and from there to the printing material. The different games are specially prepared - some take on color, the others repel it. Because the elements to be printed and the non-printing elements are on one level, the process is called flat printing. As with our printers, the four basic colors C-M-Y-K are used; for each a separate printing plate is created.
Offset printing is the most common planographic printing process, distinguishing between web offset and sheetfed offset. The sheetfed offset printing is suitable for small and medium runs, in web offset, however, can be high volumes, eg. As of newspapers, catalogs and directories, produced. Most brochures and flyers of large companies are therefore manufactured in offset printing.
The most obvious advantages of the offset printing process are its speed and cost-effectiveness: a web offset press achieves up to 65,000 cylinder revolutions per hour and can therefore produce print products in millions of copies at low cost and in a very short time. Even in digital printing, which is continuously optimized, this level is far from being reached.
3. Digital printing - in the fast lane for more than 20 years
Printing documents from home is self-evident today. In the process, digital printing, which enables us to do so, did not emerge until the 90s, together with the first printers! Since then, this printing process has been on the road to success - and continues to evolve.
Strictly speaking, in digital printing, only the artwork itself is digital. In contrast to all other printing processes, you do not need a fixed printing block (non-impact printing). The printing process itself is a mechanical one: common methods include ink-jet printing (inkjet), which sprays tiny colored drops of ink onto the paper, and laser printing, which uses the principle of electrophotography. A copy of electrical charges is generated and loose color toners are distributed on selected areas.
Digital printing is accessible to anyone who owns a laser printer or inkjet printer: Private users, offices and large businesses print everything from personalized invitations and glossy photos to large format booklets.
With special large-format printers, digital printing is now also conquering the industry. HP, for example, introduced HP PageWide printers with printing systems and web presses that work with a fixed printhead, enabling completely new and much cheaper monochrome and color large format prints.
Digital printing is particularly appealing when it comes to small volumes and personalized print objects: While other printing processes are often worthwhile only for large print runs, almost nothing has to be prepared for digital printing - there is hardly any other printing process so economical! In contrast, digital printing is quickly reaching its limits with special formats ...
4. Gravure - the printing process of our banknotes
Gravure printing has a long tradition: many of the most well-known works of old masters were engravings and thus in the 19th century the first harbingers of gravure printing. Even today, gravure has its place in the art scene.
Gravure printing is a direct printing process. In contrast to the high-pressure, it is not the high-lying but the lower-lying sections that are printed: Engraving, laser or etching create so-called "cups" which are filled with paint. The non-recessed area is removed from excess paint using a "squeegee" until color only collects in the recessed areas. This is finally transferred to the paper or printing object under high pressure.
Due to the time-consuming production of printing plates, this technique is used today mainly for printed products which are produced in large numbers - for example catalogs and magazines, but also carrier bags and foils. Banknotes and many of our stamps are also made by gravure printing.
Many gravure products impress with rich color and high print quality. The frayed edges ("sawtooth effect") that are typical for the etching process are often even deliberately used in art prints. In the field of everyday printed products, however, gravure printing is increasingly being overtaken by cheaper and more flexible offset printing.
5. Screenprinting - unsurpassed in color intensity and brilliance
Do you know the silkscreen still from school? Or did you rub ink in a nursery with a toothbrush through a sieve? Then you have already tried the principle of the printing process ...
When printing through the color is pressed by a strained sieve or a textile fabric on the object to be printed. This covers certain areas on this stencil so that no paint penetrates. For the different colors of the motif accordingly differently treated stencils are needed. The color application varies depending on fineness and fabric structure.
In addition to the use in the school and in the field of art, screen printing - the most common form of printing - is often used for textile printing and for different advertising materials. So you count z. As in flags, billboards or stickers often on the striking, color-intensive effect of screen printing products.
Via printing technique can be printed on all possible forms that are not suitable for other printing processes -. As well as bottles or dishes. The strong, intense colors that this printing process allows, however, are faced with costs that add up quickly for long runs. For this reason, the screen printing process is used above all for small to medium runs and particularly high-quality projects.