Screen printing
Silkscreen printing is a type of screen printing. The ink is not applied on the printing plate (forme) and printed back on the substrate, as in the case of the other techniques, but it is pressed through it. The screen printing is the only method of its category and its principle is unique.
It is a method developed in 1929 in the USA from where it was transferred to Europe after the WW2. However, the principles of this method are much older and the method was invented in China.
Screen printing is based on pressing of the ink through the mesh (screen). The screen is made of a frame over which a mesh is stretched, like a painter's canvas over its frame. The most used mesh materials are: uhelon, nivold, silk, or metal fibres. The screen is modified so that some of the areas (according to the design) are blocked-out to avoid ink penetration. If a multi-colour theme is to be printed, separate screens with own designs must be prepared for the individual colours. The design is transferred to the screen using various techniques. However, the most frequently used is the photomechanical method.
When the mesh with the design is prepared, the printing process may be started. At first, the ink is applied and using a floodbar it is pressed through the non-blocked holes in the mesh to the substrate. The floodbar is made of a robust handle (wooden, metal, etc.) and a rubber blade.
The Screen printing may be applied on a variety of substrates like paper, metal, plastics, or cloth. The substrate range is probably the largest from all the available printing techniques. This method is very popular specifically for printing on cloth since it creates a high-quality, lasting print. The cloth can be then washed and ironed as required without influencing the print quality.
In general, the screen printing applies much thicker ink layers on substrates than any other printing technique. It matches with the range of the printed products. The screen printing is most frequently chosen for printing posters, covers, self-adhesive labels, etc. It is used also for printing of CD/DVD covers or cloth. Its use is really versatile.
The silkscreen printing advantage is thus a variety of substrates. There are also few disadvantages. At first, it is a lower efficiency of silkscreen printing machines. Recently they experienced a huge development and there are also semi-automatic and automatic machines except of the manual ones, but the efficiency is still lower. Another disadvantage of this technique is a long drying time of printed materials and inability of printing enough sharp and fine details. Therefore it is not possible to use this method for printing of e.g. photos.