Our organization hosts softball tournaments. We're just getting in to printing tournament tee shirts. We have a company that is supplying us shirts with an image on the front and we're using a heat press to add a list of teams to the back using JetPro Softstretch Light inkjet paper. The paper works fine on our white and light pink shirts but leaves and adhesive ghost image on our darker shirts. We are only using one color(black) in our print. What product would you recommend that we use for darker color shirts? Is there something out there for inkjet printers that won't leave that rectangular image on the shirt? Any help would be greatly appreciated by this newbie.