Adhesion - Intercoat

Problem

Delamination between coats

Whitening of film between coats


Solution

Ensure correct sanding between coats

Allow correct dry time of sealer coats

Use correct finishing system

Ensure no contamination on previous coat

Apply a wet coat material

Do not fog or mist coating to apply thinner film builds

Adhesion - Stain

Problem

Delamination to stain

Whitening of film between coats


Solution

Reduce application of stain

Ensure sufficient wiping of stain

Allow correct dry time of stain

Dark stains should be obtained by using toners before stain application

Avoid heavy shading

Make sure to use the correct finishing system (sealer/topcoat) to match stain

Apply wet coat of sealer or topcoat

Do not fog or mist coating to apply thinner film builds

Adhesion - Substrate

Problem

Removal of film to substrate

Delamination to substrate when impacted


Solution

Ensure correct sanding of substrate

Use correct finishing system to match topcoat with primer used

Ensure no contamination on substrate

Apply wet coat of material

Do not fog or mist coating to apply thinner film builds

Closed grain hardwoods should be well sanded before use

Higher solids finishes need a better wood profile to anchor to than low solids

Ensure sand paper is not worn

Air Entrapment

Problem

Bubbles from pores in the wood

Air entrapment from preparation of paint

Air entrapment from application

Blistering from drying techniques

Topcoat attacking previous coat


Solution

Use defoamer

Use slower solvent balance

Change airflow during drying, check for drafts

Reduce air pressure during application

Spray thin wash coat as first coat

Ensure adequate flash off before oven

Reduce viscosity

Bring lacquer to room temperature

Use correct thinner

Use weakest solvent for previous coat to avoid blistering

Reduce recirculation speed

Reduce film thickness

Bénard Cells

Problem

Cell pattern in finish

Color and surface irregularities


Solution

Add dispersant

Add silicone additive to reduce surface tension

Increase application viscosity

Lower application thickness

Add thixotrope or thickener

Bleeding

Problem

Color migration from coated substrate

Color in sanding dust

Colored film on surface


Solution

Avoid bleeding dyes and pigments

Use vinyl sealer to seal color

Change from acid catalyzed material

Blocking

Problem

Sticking together of panels when dry


Solution

Reduce film build applied

Increase or ensure recommended dry times are followed

Ensure ovens are at the correct temperature

Increase or ensure correct airflow during dry

Ensure correct temperature of substrate

Decrease or ensure correct temperatures at stacking

Blooming

Problem

Hazy deposit on film

Oily or wax-like substance on surface

Reduced gloss

Mottled or non-uniform surface


Solution

Adjust catalyst level – over–catalyzation

Do not use stearated materials such as lacquers and certain polyesters under acid catalyzed coatings

Check formula for incompatibility

Check substrate for contamination

Blushing

Problem

Whitening of surface

Lowering of gloss


Solution

Reduce humidity

Use richer thinner

Check water level in equipment

Warm lacquer to room temperature

Increase temperature of application area

Slow dry time

Dry waterborne stains or sealers

Brittleness

Problem

Poor coin scratch

Delamination of film when impacted


Solution

Ensure that brittleness is not lack of adhesion

Check with representative

If a catalyzed system, check ratio

Brown Spots

Problem

Brown spots in film


Solution

Clean air lines of oil contamination

Drain or repair oil separator

Bumps and Sinks

Problem

Uneven surface appearance

Low depth of image (D.O.I.)


Solution

Add silicone flow additive

Add thixotrope