Lithography (Lithographic Printing)
The lithography system is based on the principle that the oil and water do not intermingle, obtaining areas that can be printed or cannot be printed on over the same surface. The section of the printing surface on which the printing will be made draws the ink and the other part draws the water. The main principle of Alois Senefelder who invented this kind of printing was: when something is written on a porous limestone with oily ink, the oily ink is avoided spreading with the application of an Arabic gum dissolved in water. Some of the solution of gum and ink penetrates on the stone.
If the surface of the stone is cleaned and watered with a sponge and an inky roll is placed on it, the oily ink on the roll is marked on the surface of the stone during the first process and the absorbed part will be accepted by it. The other wet areas of the stone, rejects the ink. Therefore, the form made on the stone occurs again. This form is transferred on a paper by means of printing.
The lithographic patterns prepared on the stone are used only with the typical litho machines. In this printing system, determining the pictures and writing on the stone as REVERSE is about having a special habit for reading and writing them.
Stone is heavy. It is a kind of calcium carbonate. It’s most important characteristic is absorbing water and oil. Lithography printing machines work very slowly. Since their patterns are heavy, it takes a long time to clean and prepare them for printing.
Tiefdruck Printing (Gravure-Intaglio Printing)
This is the most developed industrial printing technique in the world. It serves in magazine publishing, textile and especially packaging sector. It’s most important characteristic is that, it can make indefinite printing. (Because the printing is made on the flat cylinder, etek-grips sections will not be available, the whole surface of the cylinder prints completely.)
As understood from its name, gravure “means intaglio printing in German”. The photos, patterns, writings are made by engraving the copper cylinder by means of
Since copper is not durable, chrome is covered on it. Therefore, the works with high circulation are printed. Its ink is in liquid state. In this system, the parts where the ink is taken and passed on the paper are in a hole. In this system, it is necessary to work more carefully than in the offset and letterpress to acquire a printing which is close to original.
Flexo Printing (Rubber Printing)
This printing is also a part of the “high” system, like the “letterpress” printing. The printing is made with the flexo patterns. It is mostly used in the packaging sector. The printing is made on the nylon or metal folios. Therefore, the flexo printing must be distinguished from the gravure printing. In this printing technique, the density difference between point side and the center is as in the letterpress printing. Also since liquid paint is used in this technique, this difference can seen more significantly than the letterpress printing in certain situations.
The flexo printing machines are “ROTARY” and they make printing on the plastic in bobbin or paper. In this printing technique, only rubber patterns were used years ago, and it was called rubber printing at that time. Rubber pattern is used only for rough works today. Sensitive and multicolor paper and folio printings are made with trams of 48 pieces with photopolymer stereotypes and even 54 pieces. The paints used are used with diluters in aniline with the consistency of ayran and based on the basis of ethanol and they need to dry very quickly. The paint unit in this printing system is quite simple. The feeder roller revolving in the paint reservoir transfers the paint to the roller with tram and the roller with tram transfers this to the pattern boiler. The pattern boiler touches with the printing boiler and forces the paper or folio passing in between.
The flexo printing machines work quite fast. Since the way of working is simple, this system is economic. The photo films may compete with gravure in some works, if not all works, thanks to the high quality created from the stereotypes. The flexo printing system services mostly for the packaging industry.