Thanks, PE. I will check into that.
Last night I made a coating that has turned out to be very fogged. The PET was washed very well in fresh water, so I don't think that was the problem. It was a small coating, about 10 or 12 ml, as I wanted to try photo-flo (5 drops) again and glyoxal plus erythritol . Now I forgot to dilute the glyoxal and used 1 ml full strength. Anything to point to there as a foggant? I'm suspecting the stock strength glyoxal since I have used photo-flo and erythritol before, although not together, without problems.
The good news is that while this coating is unusable for photographs, its adhesion properties are very good.