Different processes have different requirements for inks, and they must also add appropriate supplementary components to the ink to make them easier to use in specific applications. For example, offset inks are more viscous and have better water resistance; gravure inks are relatively thin and fluid. Good; screen inks must have good permeability.
The main difference between the inks used in different processes is that the additives contained in the inks are different. This article will mainly focus on screen inks and pad printing inks.
In terms of substrate suitability, screen printing has great advantages, especially in the amorphous plastic hardware and direct consumer goods industries. Screen printing has been widely praised. However, there is no universal printing method in the world, and screen printing is no exception. In the area of ​​industrial printing on the surface of small areas and irregular substrates, silk screen printing encountered real troubles, and this trouble caused the birth of pad printing technology. It can be said that although there are great differences between pad printing technology and screen printing, the industries involved are very similar.
The earliest printing inks were replaced by screen printing inks. Practice has proved that there is absolutely no accommodation. However, inks used in different printing environments must have different applicability. For example, pad printing inks do not require users to have the permeability of screen printing inks, but they are required to have better thixotropy and surface dryness. To ensure that the transfer process from the steel plate to the plastic head and substrate is more accurate. The use of special pad printing inks will undoubtedly make it easier to improve the print quality.
MARABU pioneered the development of special pad printing inks. The surface tension of the ink is maintained within a constant range by the action of a mouth-feeding agent so that the ink transfer during the printing process remains absolutely consistent.
The ink transfer process is closely linked with the nature of the print head. The surface tension of the print head is controlled within a similar range to that of the print ink. This appears to be a systematic project. The essential purpose is to improve the ink transfer efficiency. The Japanese have solved this problem from another angle. They installed a plastic head cleaning device on the pad printer. However, the installed plastic head cleaning device mainly controls the amount of ink transferred, and the transfer efficiency has not improved.
MARABU has 6 (actually 8) pad printing inks to choose from: GL, mainly used on metal, ceramic, glass surface, basically a two-component ink, need to add GLH hardening, TPR, is in SR The improved printing inks based on the series of screen printing inks, the materials that can be used by SR can make TPR in the printing process; the same reason, TPY is an improved printing ink based on PY series screen printing inks; TPU ink can be used for the surface of the material that is very difficult to print; TPT is a pad printing ink mainly used in pad printing machine; TPL has better stability and can maintain good uniformity under long-term friction conditions. There are two kinds of TPP and TPS.
It is worth noting that screen printing inks and pad printing inks are completely universal, but only need to add additives to change the printability. Therefore, when there is no special pad printing ink, screen printing ink can be used instead.
Source: Screen Printing Industry