Looking for a company that sells or makes colored UV powders(UV power
should fluoresce under baclk light). These
powders should not glow in the dark. They should be able to be mixed
with a base to make a paint. When mixed with a transparent base the
substance should be clear (not visible) under normal light. Bulk
purchasing is fine. Company most likely is not located in the US, most
likely in Japan or China. I would prefer a private answer ( I know
this is not explicitly available but if you were to find the answer
and reply I am sure we could figure out a way ).

Generically, these materials are called ?phosphors? (not phosphorus).
Searching, including ?manufacturer? or something similarly
appropriate, you?ll get links like this one

http://www.americanelements.com/ph.html

Some of these materials emit in the visible when stimulated by UV.
Many of them are a wee bit nasty though and shouldn?t be open to the
air, or the hand.

Best