spray over rollers

Most likely to be an antioxidant , translated that is an oil but one manufactured to prevent the ink from skinning in the tin or on a press during a stop (lunch) .
Why is it being used in this way is probably because they dont know what reducing paste is and are reducing the vehicle with it , or basically thinning the ink a bit , if you use too much you slow the drying of the job and the colour will weaken .

Tuboruss,”back in the day” we use to call it “antiskin”
which sounds like an oximoron but it’s not.
Pam works just fine it’s a lazy mans approach to gain time befoe cleaning the press properly. Once when I resurected a cast iron waffle press and got it back on the stove and the waffles were sticking My son exclaimed I needed SPAM. really he meant PAM. So there you have it in a clam shell. best james

James …. Antiskin is a brand still kicking around .