Auto body repair & detailing: BLEND SOLVENT, dear michael, urethane

Question
Dear Michael what does 1K Urethane solvent used for?

Answer
WITHOUT ADDITIONAL INFORMATION I CAN'T ANSWER THE QUESTION.
URETHANE SOLVENT.....SOUNDS LIKE YOU HAVE A REDUCER THAT GETS ADDED TO THE PAINT MIXTURE.

NEED BRAND NAME AND PRODUCT NUMBER TO ANSWER IN FULL.

IT MAY ALSO BE A PART OF A 1K PRIMER WHICH REQUIRES YOU TO MIX A SPECIFIC AMOUNT OF REDUCER  TO
THE PRIMER TO MAKE IT SPRAYABLE.