The universe of the printing press is extremely extensive and you can find different methods, processes, systems and machinery to make prints on a wide variety of materials, with a completely different print quality. Among the most well-known and used printing systems around the world can be found rotogravure, digital printing, screen printing, letterpress printing, 3D printing, among others.
Rotogravure (also known as rotogravure in some countries of the world) is a printing process or system that uses relief engraving as the main technique, this can be done through chemical or mechanical processes with the participation of machinery, ink and the material on it. printing will be done.
This process is widely used in the world of printing due to the number of positive characteristics that allow us to adapt very good quality prints to a wide variety of completely different materials, something that can clearly offer us many advantages.
This printing system has a quite interesting and very complete history, it is said that its origin is due to another printing system that was previously known: intaglio. The first appearances of this method are located between the fourteenth century and the fifteenth century and something that few know is that before the existence of intaglio, another method called nielado (a technique for engraving on silver and other metals) was used first. But the true creator of the technique today known as Rotogravure was Karel Klik who founded the first company that used this printing process in 1895 together with his partner born in England: Samuel Fawcett.
Over the years this type of printing was taking on great importance throughout the world and from 1910 onwards it began to be used to publish newspapers or periodicals, it was first used by a German newspaper and only two years later (in 1912 ) the New York Times newspaper decides to use intaglio as its main printing system. A few years later, almost 40 different newspapers in the United States used this methodology invented by Klik. Then its uses were diversifying and different companies have been using it to print containers, wrappers, boxes and many other materials, thus becoming one of the most important processes in the world.
Rotogravure Printing Process
The first thing we must understand about the rotogravure printing process is that the process involves mainly four important elements: a container for the ink, a cylinder used for printing, a cylinder with small gaps (which are engraved through a process in the using laser technology) and a doctor blade. The intaglio process explained quite simply consists of the following:
The engraved cylinder begins to rotate in the ink container and the engraved gaps fill up with the ink. At that time the cylinder used for printing also rotates, while any excess ink is removed from the engraved cylinder using the doctor blade. The pressure exerted between both cylinders allows the material that passes in the middle of both to be printed on, thus allowing quick and easy printing. Then, as a final step, the printing must go through a drying system that usually consists of hot air currents.
What is printed with rotogravure?
The applications of rotogravure are very diverse and can be used in different market sectors:
- For the printed press, that is, newspapers, magazines and other types of publications (although other processes can also be used today).
- The most important applications of gravure consist of printing on containers, wrappers, decorative papers, among other things.
- Rotogravure can also be used to print on paper money.
Advantages and disadvantages
- It can be printed on almost any material we can think of.
- Gravure prints are highly detailed, this means that it is one of the systems that offers the best print quality.
- The constancy of the color during the printing process and in the result obtained.
- One of the best methods for large scale printing.
- It offers the possibility of printing in different types of colors without them being covered or overlapping (more than four colors without problem).
- The maintenance of the machine used for gravure is much easier and the cost is lower.
- It can be an expensive process.
- It is not at all recommended in the case of small-scale printing.
- Some of the inks used in the process can have negative effects on the environment.
Different intaglio techniques
As for any printing system, there are different techniques or processes that can be followed in gravure and that largely depend on the machine we are using. Although there are different intaglio techniques, the process remains the same (the one discussed above) and at present the most widely used technique is that of mechanical methods (although the technique of mechanical methods is also used in some companies and countries. chemicals).
Rotogravure and flexography
There are some quite important similarities between two printing processes such as rotogravure and flexography, despite this there are some important differences that we will discuss below:
Differences between rotogravure and flexography
- Flexography uses direct printing techniques and the inks are fast drying.
- Flexography is a very good technique for a small number of lower prints, but if we need large-scale prints, gravure is much better.
- The prints made with the gravure technique have a much higher quality than those made with flexography.
What inks are used?
The inks used in this process are quite similar to those used in flexography and have the following characteristics:
- They are fast drying inks.
- They have very low viscosity.
- They do not have a high presence of fats.
- They are usually quite counterproductive for the environment.
- One of the most interesting characteristics of the inks used in this printing process is that the different colors that we print on our material do not cover up, they simply add up.
- There are specific inks for special cases. An example of this can be fluorescent inks.