After I wash my shirts a few times, the ink starts to come off.
This means that you have not cured your garment correctly. Plastisol inks need to be heated to a pre-determined temperature for a certain duration of time, usually somewhere between 45-60 seconds. This would be to either to flash dry or to use a conveyor dryer. Different inks, or special garments may need their timing fine tuned. The temperature and times will vary some job to job, so always do a wash test. A great way to test to see if the ink is cured or not is to pull on the t-shirt. If the ink sticks together like plastic or rubber, then it is cured. However if it cracks and you can see the t-shirt under it, you need to increase your curing time. via Wicked Printing Stuff, your home for screen printing equipment and supplies – FAQs.