Basic Screen Printing Process
01. Creating A Design
02. Printing A Design
03. Choosing A Type Of Screen
04. Degreasing A Screen
05. Applying Emulsion
06. Screen Registration
07. Exposing A Screen
08. Washing Out A Screen
09. Taping A Screen
Now that we’ve finished printing our shirts, it’s time to clean up. For me, this is the most important part because if you take the time to clean your equipment properly, you’ll achieve better results while printing and your equipment will last a lot longer. Cleanup is going to depend on if we are saving the screen for future use, doing a color change or reclaiming the screen.
We’ll start by putting on a pair of disposable gloves and clean out the ink from the screens. We’ll need to remove all the ink from the image area but we won’t have to worry about completely removing all the ink from the screen because we’re going to be saving this screen for future use. As long as the screen is stored in a dark, cool & dry place, the ink won’t cure or dry because it is an oil-based plastisol. I use a disposable ink card to remove the ink from the screen and put back into the ink container. Use that same ink card and remove all the ink off the squeegee as well. What’s really nice about these ink cards are they are flexible which allow you to pick up most of your ink with ease and then when your done, just toss them away (at just $0.07 each, it’s cheaper then using cleaning chemicals which cost about $0.10 – $-0.15 cents each time).
After all the ink is out of the screen we’ll do an on press clean (dry wash) using Screen Wash 147, which is great for removing and cleaning plastisol inks. Lay a junk t-shirt over the pallet (this is done to protect the pallet) and place the screen in the print position. Spray some Screen Wash 147 on the screen and onto a rag, paper towel or junk t-shirt and rub into a small area of the screen. If there is still some residue left on the screen, rub using a clean portion of the rag and then use the dry portion to wipe away. Continue doing this on the entire screen and frame. If you are reclaiming the screen, you don’t have to be as thorough as if you were doing a color change. If we were doing a color change, we would untape the registration marks, spray some screen opener on the screen and scrub all the ink residue off both sides with a dry rag. Next, we’ll wipe down our press with a clean rag sprayed with Screen Wash 147 to remove any ink or adhesive residue. Lastly, we remove the old pallet tape and replace with a new sheet.
If we were reclaiming the screen, we would do a screen wash (wet wash) instead of doing an on press clean. We would still remove all the ink from the screen using a disposable ink card, and then we would take it to our washout booth. Leave the tape on the screen and get the screen wet. Spray some Screen Wash 147 generously onto the screen and scrub brush, then start scrubbing the screen, which will start degrading the ink. Make sure to clean the sides of the frame as well. Spray from top to bottom with a hose to clean off the screen wash. Now take off the tape, turn the screen around and repeat the process, but use the power washer to clean out the registration marks. Wash out the scrub pads with water and wash down the wash out sink as well before removing the emulsion.
To remove the emulsion from the screen, start by getting the screen wet on both sides with water. Spray some ER/80 on both sides of the screen and onto a scrub brush. The ER/80 is a concentrated formulation designed to penetrate and break down all types of emulsion. I mixed about 1/3 of the concentrated ER/80 into a 32oz spray bottle and filled the rest with water. Scrub both sides of the screen and let the screen sit for 2 minutes. Never let the emulsion remover dry on the screen, as this will chemically lock the emulsion in the screen and most likely render the screen useless. Using a power washer, spray the screen from the inside to remove all the emulsion. You may need to scrub the areas where there are thicker areas of emulsion to be able to spray the emulsion out.
After removing the emulsion from the screen, I like to dehaze the screen to remove any ghost images from the screen and to degrease the screen. I spray some Liquid Renu-It onto the wet screen and scrub brush. Work in on both sides of the image area, then the rest of the screen and let sit for 5 minutes. Wash out with a hose, then a power washer and again with the hose to remove any oils left from the power washer. Place the screen in front of a fan to dry and wash out the scrub brush and wash out sink.
- Be sure to use a different scrub brush for each chemical, so they don’t counteract each other. I like to label them with a permanent marker so they don’t get mixed up.
- Be very careful not to get the plastisol ink on anything that you value because the likely hood of it coming out is not very good.
- Do not wash rags in the washer machine or tub.
- Do not attempt to wash out ink from screen with soap and water as it will not work and you will risk rinsing out your emulsion.
- We suggest using plenty of paper towels to clean up.