Loss of gloss

Description of problem:  21-_loss_of_gloss.jpg
    The gloss of a refinish is evaluated according to the sharpness
    of the reflected image.  A smooth surface reflects like a
    mirror.  Any loss of gloss is generally due to the formation of
    irregularities in the paint film which lead to the scattering of
    the reflected light and that means a loss of sharpness in the
    image formed at the surface.

 

Causes:         
    – See section on cracking.
    – See section on moisture blisters.
    – High film thickness.
    – Too much air humidity during application.
    – Solvent sensitive substrate.
    – Incorrect mixing ratio or contaminated hardener.
    – Use of unsuitable thinner.
    – Insufficient airflow in the spray booth.
    – Interrupted baking.

 

Preventive measures:
    – Follow application recommendation.
    – Close hardener cans firmly after use.
    – Ensure sufficient airflow in the spray booth.
    – Do not interrupt baking cycle.

 

Remedy:
    – Sand and polish.
    – Sand and repaint.