Japanman . . .
Just need some clarification . . .
Good advice about not drinking from a cup made with epoxy resin.
I am assuming your references to amine release are applicable only to EPOXY resin, and not to polyester resins. I also advise anyone working with epoxy resins not to work without some type of ventilation, and also avoid repeated skin contact with epoxy.
Sanding of epoxy should involve wearing a mask. It's possible for a person to become sensitized and allergic to epoxy resins (or epoxy paints), and if that does occur, it is not reversible.
However, when you are dealing with polyester resins, my understanding is that the "smooth finish" you speak of after resin cures actually IS a type of wax, which is only present in "finishing resin". The purpose of it is to insure a surface which hardens and feels dry, and not sticky to the touch.
The "wax" (not sure of it's chemistry) will "float" or migrate to the outer surface when the resin is curing, and remains there if undisturbed. When trying to repair, or laminate to, this type of resin, it is necessary to use a solvent (like acetone) to remove the wax before attempting to sand and bond another layer.
On the other hand, you have polyester "laminating resin" which does NOT have the wax present, and a layup done with this type of resin will often be slightly sticky to the touch, and can gather dirt. The sticky surface is actually partially uncured resin, which bonds more readily with the next layer of laminating resin, or with a final layer of finishing resin.
Regards,
Al Parry
[email protected]