Definition
A milky, cloudy, or hazy discoloration that appears in a freshly applied lacquer or dope finish, caused by moisture trapped in the film as the solvents evaporate and cool the surface below the dew point.
Plain English
When paint or dope is sprayed in humid conditions, the surface can cool enough to pull moisture out of the air, leaving a foggy white film in the finish instead of a clear, even coat.
Context Anchor
Seen in aircraft finishing, fabric-covering work, paint inspection, and maintenance discussions about coating defects.
Derivation
From the everyday word 'blush,' meaning a reddening or change of color in the face. In finishing work it was borrowed to describe a finish that 'changes color' on its own — turning cloudy or whitish as it dries.
Why Pilots Care
A blushed finish is weak, porous, and cosmetically poor. Technicians need to recognize it because the affected area usually has to be reworked — either by adding a retarder to slow drying, or by stripping and refinishing — before the aircraft can be returned to service with an acceptable finish.
Grounding Statement
On a humid day, a drying coating can turn cloudy because moisture gets caught in it before the surface cures properly.
Intuition Check
Do not read “blush” here as a red color in someone’s face. In aircraft maintenance, blush means a cloudy or milky defect in a finish coating.
Example Sentence 1
The technician noticed blush forming on the freshly doped fabric and added a retarder to the next coat to slow the drying time.
Example Sentence 2
After wiping the blushed area with solvent, the painter reapplied the topcoat under drier conditions.