Blooming appears as dull haze or a white or oily film that dulls gloss. It comes from additives migrating to the surface, such as waxes or degassing agents, or from combustion products in direct gas-fired ovens reacting with the film, which hits epoxies and hybrids hardest. Cure conditions, oven venting and a powder change usually solve it.
The black hybrid has a bloom on it right out of the oven, wipe it and the gloss comes back.
Bloom that wipes off and comes back after the next cure points at the oven atmosphere rather than the powder.
Also heard as
- blooming
- haze
Related terms
Gloss
How mirror-like a finish is, read with a gloss meter at a fixed angle, usually 60 degrees.
Hybrid
Powder that cures an epoxy resin and a polyester resin together, trading some outdoor life for low cost and good flow.
Yellowing
A yellow shift in whites and light colors caused by overbake or by fumes in gas-fired ovens.
Overbake
Cure that went too hot or too long, causing yellowing, gloss loss and brittle film.