What is a Flash Dryer Unit?
A flash dryer is used to dry screen print ink to the touch, and not as much to cure the ink like a conveyor dryer. Screen print ink needs to be dried to the touch to apply multiple colors and prevent them from bleeding together. Screen printing onto colored garments requires an underbase to first be printed so the colors look opaque on the shirt. After the white underbase is printed. it must be dried using a flash dryer so that other colors can then be printed. Because a flash dryer must hover over the print pallet, it takes up the space of a screen. So, if a press has 6 heads and 4 stations, then the most amount of colors it can print is 5 because a flash dryer requires the space of a screen. On an automatic press you will only be able to print 4 colors as the head after the flash will be left open as a cool down station. If there is no cool down, then the ink in the screen next to the flash will begin to gel due to heat.
How to Choose the Right Flash Dryer
Some flash dryers feature auto swing features that can be controlled using a foot pedal. These types of flash dryers are more ideal for manual presses, whereas automatic presses typically require a specific flash dryer so that it fits perfectly with the equipment. The last variable to think about when purchasing a flash dryer is the actual size of the heating element. As you would think, the bigger the size of the heating element the higher the price of the unit. It is important that the flash dryer’s heating element be larger than the largest potential print area. So it's a good idea to buy a flash dryer that is large to avoid potential problems.
Why Buy a Higher Quality/More Expensive Flash Dryer
It is important to know that not every flash dryer is created equal and you get what you pay for. A quality flash dryer will deliver consistent heat throughout the entire heating element with little temperature changes. Because flash dryers must hover over the print area it requires a very sturdy base and support pole. Cheaper flash dryers often have issues being able to support the heavy heating element to be perfectly parallel with the palet, which is very important to dry the ink at the same temperature. The equipment itself is fairly simple as it is primarily just a heating element made up of coils just like what is inside a conveyor dryer. Another way to think about it is that a conveyor dryer contains 2-20 flash dryers inside the chamber.
