TDS
TECHNICAL DATA SHEETTECHNICAL DATA SHEET
ACRYLIC-ALKYD ENAMEL UNDERCOATER
NO. 437
PRODUCT INFORMATION
BEHR® Acrylic-Alkyd Enamel Undercoater is a water-based alkyd primer that has excellent tannin stain-blocking and outstanding
ow and leveling. It provides great sandability and is designed for use under higher sheen paints. This high-hide product also
oers corrosion and rust resistant properties to properly prepared ferrous metal.
RECOMMENDED USES:
This primer is recommended for use over properly prepared uncoated and previously painted interior/exterior surfaces. Ideal for:
• Drywall/Gypsum Board • Wood • Engineered Wood • Composite Wood
• Ferrous Metal • Vinyl
COMPLIES WITH THE BELOW AS OF 10/1/2020
SCAQMD YES LADCO
YES
CARB SCM 2007 YES AIM
YES
OTC PHASE ll YES MPI
137, 172
OTC YES
PRODUCT SPECIFICATIONS:
Tint Bases/Max Tint Load:
No. 437 126 oz / 4 oz
Resin Type: Alkyd-Acrylic
Weight per Gallon: 11.2 lb
% Solids by Volume: 39% ± 2%
% Solids by Weight: 54% ± 2%
VOC: < 50 g/L
Flash Point: N/A
Viscosity: 92 – 102 KU
Recommended Film Thickness:
Wet: 6.4 mils / Dry: 2.5 mils @ 250 sq ft per gal
Wet: 4.0 mils / Dry: 1.6 mils @ 400 sq ft per gal
Coverage: 250 – 400 sq ft per gal depending on application
method and substrate porosity. Does not include the loss of
material from spraying.
APPLICATION:
Brush: Nylon/polyester
Roller: 1/4" – 1/2" nap roller cover, depending on surface
texture
Airless Spray:
Tip: .015" – .019"
Filter:
60 mesh
Fluid Pressure: 1,800 – 2,500 psi
Thinning: Do not thin if using a roller or brush; however,
if using a sprayer and thinning is required, thin with clean
water at a rate of no more than 1/2 pint of water per gallon.
Dry Time: @ 77°F & 50% RH
Longer dry time may be required in cooler temperatures and
higher humidity.
To Touch: 30 minutes
To Recoat: 1 hour
SURFACE PREPARATION:
All surfaces must be clean, free of dust, chalk, oil, grease,
wax, polish, mold and mildew stains, loose and peeling
paint, rust and all other foreign substances.
Wood: Remove mill glaze with sandpaper or use a product
such as BEHR PREMIUM® All-In-One Wood Cleaner No. 63
(exterior only) to open the pores of the wood and follow
all label instructions. For severe stains caused by mold,
mildew, algae and fungus, apply a mildew stain removing
product. Set nails and ll holes, scratches, and gouges with
the appropriate wood ller and let dry completely. Remove
all dust with a wiping cloth. Fill all gaps with a 100% acrylic,
siliconized, paintable caulking and allow to dry completely.
Patched and lled surfaces should be sanded smooth
and dusted clean prior to coating. WARNING! Sanding or
scraping pressure treated lumber may be hazardous; wear
appropriate protection.
Weathered Wood Surfaces: To remove loose wood
bers, latex, oil-based and 100% acrylic coatings on new or
weathered wood decks, siding, fences, shakes and shingles,
use a product such as BEHR PREMIUM Wood Stain & Finish
Stripper No. 64 and follow all label instructions. Use a
product such as BEHR PREMIUM All-In-One Wood Cleaner
No. 63 and follow all label instructions to clean and brighten
the wood surface and to remove light to medium stains
caused by mold, mildew, algae and fungus. Be sure to follow
all label instructions.
Steel: Minimum surface preparation is Hand Tool Cleaning
in accordance with SSPC-SP2. Remove all oil and grease from
the surface with a solvent in accordance with SSPC-SP1.
For optimal performance, use Commercial Blast Cleaning
in accordance with SSPC-SP6. Prime the area with a rust-
inhibitive primer the same day as cleaned.
Shop-Primed Steel: As there is potential for many forms
of contamination during storage and transport, a thorough
cleaning is always recommended for shop-primed surfaces.
Paint exposed areas, i.e., where shop primer is abraded,
with the same material as used for shop priming to comply
with SSPC-PA 1 for touching up shop-primed surfaces. Note:
Assess the integrity of the shop primer prior to application
of subsequent coatings. Review all coatings intended for the
project and conrm the compatibility between shop and
eld-applied coatings.
Stain-Blocking: After priming, test for stain bleed-through
by applying the topcoat to a small section. If the stain bleeds
through the topcoat, apply a second coat of primer and
test again before topcoating the entire area. If bleeding
continues, primer may need a longer dry time before
applying topcoat. On stained surfaces, topcoat in 4 hours; for
heavy stains, topcoat in 16 hours. Two coats may be needed
over heavy stains and tannin-rich wood.
Previously Painted Surfaces: Remove all loose and
peeling paint and all other foreign substances. Clean any dirt
and grease by scrubbing the surface with a detergent and
water solution, followed by a thorough rinsing with clean
water. Set nails and ll holes, scratches, and gouges with the
appropriate patching material. Let dry completely and sand
smooth. Remove all dust with a tack or wiping cloth. Fill all
gaps with a 100% acrylic, siliconized, paintable caulking,
and allow to completely dry prior to coating.
Glossy Surfaces: For maximum adhesion, sand the surface
thoroughly to provide a rough surface before coating.
WARNING! If you scrape, sand or remove old paint, you
may release lead dust. LEAD IS TOXIC. EXPOSURE TO LEAD
DUST CAN CAUSE SERIOUS ILLNESS, SUCH AS BRAIN DAMAGE,
ESPECIALLY IN CHILDREN. PREGNANT WOMEN SHOULD
ALSO AVOID EXPOSURE. Wear a NIOSH-approved respirator
to control lead exposure. Clean up carefully with a HEPA
vacuum and a wet mop. Before you start, nd out how to
protect yourself and your family by contacting the National
Lead Information Center at 1-800-424-LEAD or log on to
www.epa.gov/lead.
This information is provided “as is” and no representations or warranties, either express or implied, of merchantability, tness for a particular purpose or of any other
nature are made with respect to this information or to any product referred to in this information. For SDS or to consult with a Behr Paint Company representative,
call 1-800-854-0133 Ext. 2 (U.S.A. only). ©2020 Behr Process Corporation, Santa Ana, CA 92705 U.S.A.
Revised 10/2020
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