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Paint Defects

Blushing

Description

A whitish coat appearing on the surface of acrylic lacquer films only, during or very soon after spraying.

Cause

Blushing and bad weather are closely related. In warm, humid or cold damp weather, the evaporation of the solvents from the film lowers the surface temperature, causing moisture vapor to condense and form tiny droplets of water on the surface. The use of poor quality thinner, especially in cold, draughty areas, will also promote blushing. Fanning air over surface (spot repairs) can also cause blushing.

Prevention

Use a high quality thinner or continue with the present thinner adding retarder according to directions.

Rectification

To save the job that has 'blushed', apply a mist coat of thinner to which retarder has been added. Avoid spraying lacquers in draughts or damp, cold rooms. Do not fan air over the surface whilst drying. In extreme conditions, postpone spraying until outside conditions improve.