Builders' Forum Archives
Re: Amine Blush
Posted by Steve Miller on Jun 21, 2005
Blush occurs in certain conditions with amine cure epoxies. Some epoxy formulas do not have amine so they do not blush. Watch for so called no blush epoxy that has a temp/humidity range for its no blush claim. That means it can blush in certain conditions. As a precaution I always wet sand or water wash (warm with a 3M scrubber pad). If the epoxy surface feels slimy or waxy its blush. Personally I think the blush scare is way over-rated. It does come right off with plain old water.
Here is what System 3 says about the subject:
A surface film may form on some epoxy systems during the curing process. Technically, this surface film is an amine carbonate that can form in the presence of carbon dioxide and water vapor. More appears on cool damp days than on warm sunny days. This film, often called blush, is water-soluble and should be removed with a sponge and warm water before sanding or painting. Surface blush does not affect the clarity of the cured epoxy film.
In Response to: Amine Blush by Shuswap Pat on Jun 21, 2005
- Re: Amine Blush by Steve Miller on Jun 21, 2005