Screen printing, also called silk screening, is a way to print custom or personalized logos, text, or artwork repeatedly on t-shirts, sweatshirts, koozies, bags or any other apparel you wish to customize. Basically, a screen is imprinted with your design, placed over the item to be printed, and then ink is forced through the screen with a squeegee onto the item. The item is then place through an oven to cure the ink.
You design is placed on a screen or screens and then placed on the press. There are several types and sizes of presses; we use a 4-platen 6-color manual press. This means we are capable of printing designs with 6 colors and the ink is applied manually. The screen is clamped in the press and aligned so that the image will print in the correct place on the t-shirt. If there is more than one color then there is a screen for each color and they have to be placed on the press and each one is aligned with the other screen so that when the ink is applied, each color is in the correct position.
Once the screen or screens are on the press, now it’s time to apply the ink. The ink is plastisol ink and we use Union ink for it’s excellent quality. The specific color of ink is spread along the base of the screen or screens. A squeegee is used to apply the ink. The t-shirt is placed on the platen. The screen is put into position above the platen. To apply the ink, we first have to flood the screen with the ink by pulling a thin coat of ink across the top of the screen with the squeegee. The screen is then lowered down over the t-shirt. We use the squeegee to push the ink through the screen onto the t-shirt. The press is designed so that the screen is always in alignment with the platen. So when we are doing more than one color, the t-shirt remains on the platen, the next screen is rotated over the platen and the new ink color is applied to the t-shirt. This process is repeated for every color of the design. Sometimes, in order to print one color over top of another color, it may be necessary to flash or heat the previous ink on the t-shirt. To flash, the platen is rotated under the flash unit, which is a heater. The flash unit will heat the ink very quickly, in a matter of a few seconds, so that it gels over, which allow you to print the next ink directly over top. This is important especially when doing an underbase that all other ink colors are printed directly on. Once all colors have been applied, the t-shirt is removed from the platen and put through the conveyor dryer oven. Plastisol type ink only cures with heat, so the t-shirt has to be heated to at least 300°F to set the ink. The t-shirt is finished when it comes out of the oven, unless there is another design being printed on the opposite side and / or sleeve, then the screen printing process is repeated. This process is the same for printing on t-shirts, sweatshirts, fleece wear, koozies, bags or other apparel.