Our go to is Rutland Super Poly white, but I do have to say, we tried some of the One Stroke Versamax White. It's an all encompassing white for anything, vinyl, nylon, 100% you name it. You need no additives. It's already stretch ready, bleed resistant, and bonds to anything. It's pricey, but it's really nice, even underbasing. We did a ton of compression shirts and nylon/stretchy type athletic bags for a private line and it was nice to work with.