What sealant should I use on ceramic tile coasters to avoid tackiness?

[StephenA]

I finally got around to trying to make a set of coasters from some scrap ceramic tiles, but my clear spray sealant left them feeling slightly tacky even after days of drying. I was hoping for a smooth, wipeable finish. Did I use the wrong type of sealant, or maybe not prepare the painted surface correctly?

[Gregory61]

I tried the same with some scrap ceramic tiles. The spray coat felt fine when it dried, but after a couple of days it stayed tacky to the touch and never fully cured. I kept thinking maybe the paint layer underneath wasn’t compatible.

[BenjaminP]

I did a couple coats of water-based polyurethane, let it cure for a day between coats, and it still stayed tacky. In the end I switched to a clear epoxy resin topcoat and that cured hard, but it took longer than I expected and the scent was strong.

[Adam.H]

Do you think the real issue is the spray versus the paint, or is it humidity or temperature during cure?

[Jason_R]

I drifted into tangents about dust, oil from hands, or the tile's porosity, and went back and forth before deciding not to chase it further.