MIL-HDBK-1110
coatings. Also, latex paints do not cure well at temperatures
below 50 degrees F, as the emulsion does not coalesce to form a
good film.
Water Emulsion (Latex) Coatings
Advantages
Limitations
Environmental acceptability
Limited durability
Easy to apply/repair/topcoat
Poor chemical/solvent
resistance
Excellent flexibility
Poor wetting of surfaces
and color and gloss retention
Poor immersion service
Low cost
Must cure above 50 degrees F
Available in wide range of
color and gloss
2.3.3
Lacquers. Lacquers (e.g., vinyls, chlorinated rubbers,
and acrylics) form durable films that have good water and
chemical resistance but, being thermoplastics, poor solvent and
heat resistance. They have a low film build but dry so fast that
they can be quickly topcoated. When used on steel, they require
a blast-cleaned surface, and in some cases wash priming, for good
adhesion. They are easy to topcoat and repair and can be
formulated for good gloss retention. The good weathering of
acrylic lacquers is duplicated in acrylic water emulsion
coatings.
a) The chief disadvantage of lacquers is their high
VOC content. Because of their uniquely excellent performance on
exterior concrete swimming pools, chlorinated rubber coatings
have been granted temporary exemptions in some localities for
this use despite their high VOCs.
Lacquers (Vinyls, Chlorinated Rubbers, and Acrylics)
Advantages
Limitations
Rapid drying and recoating
High in VOCs
Good chemical resistance
Poor solvent/heat resistance
Good in water immersion
Low film build
Good gloss retention possible
Blasted surface necessary
Good durability
Occasional poor adhesion
Easy to topcoat and repair
Can be applied at low temperatures
b) Bituminous (asphalt and coal tar) coatings are also
lacquers, but they are discussed separately because of their
unique film properties. Bituminous coatings have found much use
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