Back in June, I was asking someone about these inks. They mentioned them in a thread. The person gave a fabulous answer on these inks, as well as a link.
This should definitely kick start your research and give you enough knowledge to take it further.
Beyond giving you this link describing the product and what it is called, I really don't have much more for you. I didn't persue this product at all. Here is that link with info on these UV affected inks:
http://www.t-shirtforums.com/general-t-shirt-selling-discussion/t50535.html#post298597
I have also seen around the forum or on supplier sites the color changing mugs. I would just do a search on color changing mugs here and just google the term. It's getting to be a more common product, I'm sure it won't take too much to find.
The next closest product I can mention for inkjet heat transfer is glow in the dark heat transfer paper. That is available at Coastal. If you go there and see what it is, from there, you can find more suppliers and compare prices and products. I hope you find something that works for you, and good luck to you.