Drum screen printing ink in different environments (5)

5. The influence of the surface quality of the drum
The drum surface coating directly affects the adhesion of the screen printing ink. For different coatings (such as amino-baked steel drums, alkyd-baked steel drums, galvanized steel drums, chrome-plated steel drums, and tin-coated steel surfaces Barrels) Special inks should be formulated to increase ink adhesion. In addition, cleaning the surface of the drum can also increase the adhesion of the ink on the drum surface. For example, the presence of dust, grease, and dirt on the surface of the drum will make it difficult for the ink to adhere and must be removed. 
Third, the type of steel screen printing ink 
Barrel screen printing inks can generally be divided into resist inks, plating inks and two-fluid (two-component) reactive inks. 
1. Anti-corrosion ink
The anti-corrosion inks used in drum screen printing are mainly solvent-based resist inks. 
The ink has good corrosion resistance, and finally the solvent is used to remove the film. For example: Asphalt ink, can be used on the 5th road asphalt dissolved in gasoline, to a certain viscosity, can be screen printing, low production costs; can also be thick white paint alkyd varnish, phenolic varnish, gasoline, turpentine, etc. Mixed use. 
2. Electroplating ink
The main components of electroplating ink include asphalt type, modified polyethylene type, synthetic rubber type, and thermosetting epoxy type. 
3. Two-fluid reaction ink
Two-fluid reactive inks are also called two-component reactive inks. It is the use of two components with completely different chemical properties that are mixed thoroughly before printing, and immediately undergo printing. After the printing, chemical reactions take place and the polymer is compounded to dry the conjunctiva.
IV. Practical ink conditions and problems
At present, many screen printing inks used by steel drum manufacturers can be classified into two categories:
One is a slow-drying ink; the other is a quick-drying ink. Most of the slow-drying ink manufacturers use metal offset inks. Its main formula is ink + alkyd paint + dry oil, the proportion of ink is 75% ~ 80%; alkyd paint is 20%; dry oil is 3% ~ 5%. The purpose of adding drying oil is mainly to speed up the drying speed of printing graphics after screen printing. The printing ink has strong adhesion after printing. However, the drying speed is slow. Under normal circumstances, it takes 10 to 30 mIN in summer and it takes longer in winter. Therefore, this ink is not suitable for use in the north during the winter. Another type of fast-drying ink is mainly a kind of two-liquid reactive ink, that is, the ink is composed of two parts of A and B. Before printing, B is added to A. The proportion of the added ink is based on actual production. Conditions and weather conditions. In general, we call Part B slow-drying agent. The amount of slow-drying dose added to the ink directly affects the quality of the drum screen printing. The more slowly the dry dose is added, the poorer the adhesion of the graphic after silk screen printing. However, if the slow-drying dose is added too little, it can be easily sealed during printing, resulting in operational difficulties. 
From the analysis above, we can see that the performance of the ink directly affects the effect of the drum screen printing. The manufacturer of steel drums should reasonably select the ink that meets his own production requirements according to the changes in the actual production climate in order to achieve the best results for the steel drum screen printing. (Finish)