～Foam bubbles...～
In screen printing, the ink is stirred on the screen plate with a squeegee, so air is mixed in the ink. If this remains as bubbles, it will cause various problems. Bubbles can be important in some cases, like cake, but they are generally hated in screen printing.
In normal screen printing, various methods are being considered to find out how to eliminate bubbles quickly. For example, one method is to mix a small amount of surfactant in the ink to make the bubbles break easily. However, there is a problem that if a large amount of this surfactant is added, the adhesion of the ink will decrease. So there are limits.
There is also a method of reducing the number of meshes in the screen version.This breaks the bubbles into smaller pieces as the ink passes through the finer mesh, making them more fragile. However, there are limits to this as well. There is a problem that the finer the mesh, the thinner the printing film thickness. This method cannot be used if you need to print thickly.
Isn't there a more ideal way?
What are the sources of the bubbles?
Air is the source of bubbles. If there is no air, there will be no bubbles.
That's right, you can print in space!!
But it's not realistic.
That's where the Vacuum Screen Printer comes in.
The printing machine part is in the chamber, and the air is removed with a vacuum pump before printing. Since there is no air, bubbles will not be generated even if the squeegee stirs the ink.
There is one more good thing.
Even water escapes in a vacuum. Ink that reacts with water can also be printed.
Vacuum printing is a possible printing method because it is screen printing.
