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The Value of Standards in Printing Halftone Blends

(June 2009) posted on Fri Jun 12, 2009

Garment designs that feature blends tend to attract more attention than plain decorations. Trimingham explains how to develop standards for applying blends in your printing operation.

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By Thomas Trimingham

Having quality squeegees to create a good print is a must, and you must pay equal attention to the care and maintenance of your screens. A good concept to follow is to check each screen for tension and holes after each reclamation so you can have a label that will show screens that are low in tension and that need to be isolated or discontinued. One of the biggest troubles that printers have in screen printing higher quality work is lack of control over screen tension. The biggest concern is really having an acceptable level of tension that is consistent from one screen to the next so that each screen flexes the same amount. This prevents issues with registration by requiring less squeegee pressure on press. The ultimate goal is to use the lowest pressure necessary to create a decent layer of ink that will sit on the surface of the garment rather than penetrate deep into the material (this is the case for the majority of standard screen printing applications with plastisol inks).


Testing the inks and finding the best dot

If you’re armed with great squeegees and perfect screens (or close at least), it should be a simple matter to print beautiful blends. Unfortunately, the inks can still cause some issues depending on their composition and attributes. The fundamental characteristics of your inks will dictate whether you’ll need to modify them to a certain degree to make sure they create the best blending of colors and remain the brightest during the print run (a list of these characteristics is provided in the sidebar “Ink Attributes" at the end of this feature article).

Additives, such as viscosity modifiers, are commonly used to optimize inks for halftone printing. You must take care when using additives to not mix in too much and damage the print’s washfastness or make the ink too transparent. The best method is to follow the manufacturer’s instructions and slowly add in these products to achieve the proper viscosity. It is a known fact that most plastisol inks come in the door a little too thick and tacky for perfect halftone printing. Perhaps inks are manufactured that way because it’s easier to loosen an ink with modifiers than to try to thicken it.


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