Coatings Cafe
Hiding
Defect Description
With poor hiding, the primer color or undercoat sealer is visible under the topcoat.
The color of the paint is influenced by the underlying color of the substrate due to light reflection. Hiding power is the ability of the paint to “hide” or to completely cover the substrate color. For example, paint is often applied over black and white checker board “hiding charts” in an increasing thickness film build wedge to determine the film build at which the paint can “hide” or completely cover the black and white squares. Hiding can be a complex property and is strongly influenced by film thickness and the pigment color and loading in the paint.
Also known as: opacity, poor coverage, transparency, thin paint
Possible Causes of Defect
1. Low film thickness
2. Film thickness is not uniform across the area –“thin spots”
3. Color coat not mixed properly-pigment sedimentation
4. Substrate color is not correct for application of topcoat
Tips to Avoid Defect
-
1. Apply the proper film thickness per the technical data sheet
2. Ensure the paint thickness is uniform across the area
3. Mix the paint well before using
4. Use the proper primer color for the color coat
How to Repair the Defect?
- Consult your specific paint shop procedures.
- Finesse Deck: Sand plus 2-step Polish
- Spot Repair: Sand plus Repaint