Hot Stamp Foil = HSF
Construction HSF
Layer #1 = release coat
Layer #2 = Top coat
Layer #3 = vacuum metalized metal (in 60's could have been white gold)
Layer #4 = Sizing
Sometimes between layer 2/3 and 3/4 there is a tie layer. The gold tint is yellowing from 60's top coat chemistry. In the day nitrocellulose/acrylic chemistry was used where as today incorporation of urethane and sometimes radiation cured resins are common. Light stable chemistries for HSF are still rather crude. Yes, made HSF for 10 years...... Thought I would add a factoid....
