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Click here to view Application Guide DeSoto®
conductive
technical data coatings

DeSoto® conductive coatings 528X310
• BMS 10-21 Type III
Description • CMS 565-12 Type III
DeSoto® conductive coatings are conventional solids, • BPS 299-947-142
carbon filled, epoxy-amine coatings with controlled
conductive properties. These high performance coat- DeSoto® conductive coatings are compatible with the
ings are designed to obtain surface conductivity on following primer and topcoat specifications:
non-conductive (composite and other plastics) sub-
strates. Additionally, DeSoto® conductive coatings Primers
control static charge bleed-off on radomes, anten- • BMS 10-79 Type II & III
nas, and other insulative parts. • BMS 10-103
• CMS 565-01
DeSoto® anti-static coating (528X306) is used to
bleed-off the static charge from the aircraft’s radome Topcoats
and antennas. This coating has a resistivity require- • BMS 10-60 Type I & II
ment between 1.0 to 100 megohms per square inch, • BMS 10-72 Type VIII
and requires a BMS 10-79 or BMS 10-103 primer • CMS 565-09 Type II
before topcoating.
Application temperature 65°F - 95°F
DeSoto® conductive coating (528X310) is used on
non-conductive substrates to facilitate the discharg- (18.3°C to 35°C)
ing and positive grounding of static electrical charges
to the primary structure. This coating has a much Application humidity 40% - 75%
higher surface conductivity, with the resistivity
requirement between 0.1 to 100,000 ohms per Mix ratio (by volume)
square inch. The application of a BMS 10-79 or
BMS 10-103 primer prior to topcoating is highly rec- 1 part base 528X306/528X310
ommended.
1 part curing solution 910X464
DeSoto® conductive coatings are compatible with all
conventional, airless, and HVLP spray equipment. Viscosity
For important details on the application parameters
for these primers, consult the application guide for Initial mix, #1 Zahn cup 30 - 40 sec.
DeSoto® conductive coatings or contact your local
PRC-DeSoto International Application Support Pot life (4 hours) 40 sec. max.
Center.
VOC, EPA method 24 700 grams/l
DeSoto® conductive coatings are qualified to the
following specifications: Dry film density

528X306 528X306
• BMS 10-21 Type II
• CMS 565-12 Type II 0.00773 lbs/ft2 at 1.0 mil dry film
• GMS 5003
• LES 1258 528X310

0.00804 lbs/ft2 at 1.0 mil dry film

Theoretical coverage

528X306

251 ft2/gal at 1.0 mil dry film

528X310

267 ft2/gal at 1.0 mil dry film

Recommended dry film thickness

0.6 to 1.0 mils (15-25 microns)

DeSoto® Aerospace Coatings Date issued: 8/01
Supersedes: 2/99
PRC-DeSoto International, Inc.
5454 San Fernando Road, PO Box 1800
Glendale, California 91209
(818) 240 2060 Fax (818) 549 7771

DeSoto® conductive coatings

Drying times @ 75°F (23.9°C) and 50% R.H. Note: The application and performance property
values above are typical for the material, but not
Duct free 15 min. max. intended for use in specification or acceptance
inspection criteria because of variations in testing
Tack free less than 2 hrs methods, conditions, and configurations.

Dry through 4 hrs Storage life
Inspect the condition of the container to ensure
Dry to overcoat 4 to 24 hrs compliance to FED-STD-141, Method 3011.1. The
material should be stored at temperatures between
Full cure 7 days 40°F to 115°F (4.4°C to 46.1°C) to ensure shelf life.

Accelerated cure Health precautions
This product is safe to use and apply when recom-
15 minutes flash off @ 75°F (23.9°C), mended precautions are followed. Before using this
product, read and understand the PRC-DeSoto
then 30-45 minutes at 140°F (60°C) International “Safe Handling Guide” for aerospace
coatings and the Material Safety Data Sheet (MSDS),
& 5% R.H. min. which provide information on health, physical and
environmental hazards, handling precautions, and
Color Jet black first aid recommendations. An MSDS and the Safe
Handling Guide are available on request. Avoid over-
Gloss @ 60 degrees 30 units max. exposure. All mixing and spraying must be conduct-
ed with adequate ventilation and proper personal
Spray equipment protective equipment as recommended. Obtain
medical care in case of extreme overexposure.
Compatible with conventional,
For industrial use only. Keep away from
airless and HVLP spray equipment children.

Shelf life For emergency medical information call
1-800-228-5635.
12 months from date of manufacture
For sales and ordering information call
Performance properties 1-800-AEROMIX (237-6649).

Service temperature

-65°F to 350°F (-54°C to 176.7°C) Conforms

Film hardness

F pencil minimum Conforms

Surface resistivity

528X306 1.0 to 100 mega ohms/square inch

528X310 .1 to 100,000 ohms/square inch

Fluid resistance

BMS 3-11, 30 days immersion

@ 75°F (23.9°C) Conforms

Distilled H20, 7 days @ Conforms
75°F (23.9°C)

Fastener corrosion

Salt spray for 250 hours Conforms

Rain erosion (528X310 only)

385 miles per hour exposure

with a 3 to 4 inch per hour

water spray for 30 minutes Conforms

Adhesion

Cross-hatch adhesion Conforms

DeSoto is a trademark of PRC-DeSoto International, Inc., registered with the U.S. Patent Office.

All recommendations, statements, and technical data contained herein are based on tests we believe to be reliable and correct, but
accuracy and completeness of said tests are not guaranteed and are not to be construed as a warranty, either expressed or implied.
User shall rely on his own information and tests to determine suitability of the product for the intended use and assumes all risks and
liability resulting from his use of the product. Seller’s and manufacturer’s sole responsibility shall be to replace that portion of the product
of this manufacturer which proves to be defective. Neither seller nor manufacturer shall be liable to the buyer or any third person for any
injury, loss, or damage directly or indirectly resulting from use of, or inability to use, the product. Recommendations or statements other
than those contained in a written agreement signed by an officer of the manufacturer shall not be binding upon the manufacturer or seller.

Printed in U.S.A.

DeSoto®
conductive coatings application guide

PRC-DeSoto International

Specifications Material inspection prior to use
BMS 10-21 Type II and Type III Prior to using, inspect the containers for damage or leaks
that may have occurred during shipping. The condition of
Product codes the curing solution is an important factor in obtaining the
528X306/910X464 (Type II) optimum properties from the coatings. Appearance of a
528X310/910X464 (Type III) Replacement for Type I white haze indicates moisture contamination.

Use Mixing
DeSoto® conductive coatings are carbon filled, epoxy- Before mixing any paint, the material should be allowed to
amine coatings with controlled conductive properties reach room temperature. This can be achieved by leaving
used to obtain surface conductivity on non-conductive the material in the shop for approximately 24 hours before
substrates (fiberglass and other plastics). The coatings mixing. Be sure all mixing and measuring containers are
control static charge bleed-off on radomes, antennas, clean and free from contamination. Shake the base or stir it
composites and other insulative parts. thoroughly until there is no solid material left on the bottom
of the can.
BMS 10-21 Type II is used on radomes and antennas and
has a resistivity requirement of between 1.0 to 100 The mix ratios of Type II and Type III products are one to
megohms per square. one by volume. Mix one part by volume of base with one
part by volume of curing solution.
BMS 10-21 Type III is used on non-conductive substrates
to facilitate the discharging and positive grounding of static Always add the curing solution slowly while stirring the
electrical charges to the primary structure. It has much base. If the material is added in the wrong order or all at
higher conductivity (lower resistivity) than Type II. The once, local areas of incompatibility can occur. This will
resistivity requirement is between 0.1 to 100,000 ohms cause the resin or vehicles to “kick out” into small solid
per square. particles. These particles are difficult to redisperse and
can create a rough surface or cratering.
Surface preparation
Thorough surface preparation and cleaning prior to Pot life
applying the conductive coatings is extremely important to Type II and Type III products require 30 minutes of
obtain the desired resistivity. induction time.

Follow the surface preparation instructions below before Strain the mixed coating through a fine mesh nylon cloth to
applying the conductive coatings: remove any particles that may have been introduced into
the coating during mixing and measuring. Stir the mixed
1. The surface of the non-conductive laminate should be material before and during use.
lightly sanded with a 180 grit or finer sandpaper to
remove the glossy finish. The typical pot life of these coatings at 77°F (25°C) is four
hours.
Note: The resistivity of conductive coatings is directly
related to the condition of the substrate surface. Sanded Note: The resistivity of these coatings slightly increases
and rough substrate surfaces on which the coating is during its pot life. The resistivity of a coating sprayed during
applied will lower the resistivity. Smooth and glossy the first hour of pot life can be lower than the resistivity of a
substrate surfaces will increase the resistivity. coating sprayed during the third hour of pot life.

2. The sanding dust should be removed by wiping with a Note: Discard any unused material that has exceeded its
clean rag. usable pot life.

3. Immediately before applying the conductive coating,
wipe the surface with a clean rag and a suitable solvent
such as Desoclean® 110 cleaner.

2

Spray equipment Electrical resistance test
These conductive coatings have been developed for use The following procedure is used to determine the resistivity
with conventional or HVLP spray equipment. of conductive coatings:

HVLP #91-#94 1. Prepare three panels for each test. The panels should
11-15 psi be epoxy fiberglass laminates with approximate
BINKS Mach I 10 psi maximum dimensions of 0.03 X 4 X 6 inches (.08 X 10.16 X
Tip size 15.24 cm).
Pot pressure
Atomization pressure at gun 2. Lightly sand and clean the surfaces of the test panels
according to the surface preparation procedure outlined
GRACO 1265 0.047” to 0.057” above.
11-15 psi
Tip size 10 psi maximum 3. Spray apply the coating to a dry film thickness of 0.6 to
Pot pressure 1.0 mil.
Atomization pressure at gun
4. Cure the coating either for seven days at 75°F
Coating application or flash off for 15 minutes to allow the solvent to
Spray apply these coatings to a dry film thickness of 0.6 to evaporate and then cure for 30 minutes at 140°F+5°F.
1.0 mil (15 to 25 microns).
5. Determine the resistance per square of the coating
Note: Spray technique is extremely important in controlling using an ohmmeter and 3M conductive electrical tape
coating resistivity. Dry spraying will reduce resistivity and (Copper X-1181 or Aluminum X-1170).
wet spraying will increase resistivity of the coating.
If the resistance of the coating is too high, the following
Note: Dry film thickness is another important variable in procedure is recommended:
controlling coating resistivity. In Type II applications,
increasing the film thickness will increase resistivity. a) Thoroughly abrade the fiberglass surface.

Application conditions b) Apply the coating at the beginning of its potlife.
Optimum conditions for application of these topcoats are
68°F to 86°F (20°C to 30°C) and 20% to 60% relative c) Dry spray the coating.
humidity.
d) For a Type II coating, maintain the dry film thickness
Cure conditions near the minimum specification requirement (0.6 mil).
Before measuring the resistivity, the coating must be For a Type III coating, maintain the dry film thickness
allowed to cure for seven days at 75°F (24°C). To near the maximum specification requirement (1.0 mil).
accelerate this process, the coating can also be cured at
135°F to 145°F (57°C to 63°C) for 30 minutes after a 15 If the resistivity of the coating is too low, the following
minute flash off period at 75°F. procedure is recommended for a Type II coating:

Note: Resistivity of the coating is directly related to its a) Do not abrade the surface before applying the
cure. A partially cured coating will have high resistivity. conductive coating.

b) Apply the coating near the end of its pot life.

c) Wet spray the coating.

d) Maintain the dry film thickness near the maximum
specification requirement.

Clean up
Flush equipment with Desoclean® 45 cleaner or Desoclean®
110 cleaner.
The coating is a chemically reacting system. It is no longer
soluble in solvents after it has cured. For this reason, clean
equipment as soon as possible after the coating has been
applied and always before the material has cured. Note
that even a fresh coating deposits a film on the equipment
that does not dissolve easily. Agitation with a brush or cloth
will help to remove these deposits.

Health and safety
This product is safe to use and apply when recommended
precautions are followed. Before using this product, read
and understand the PRC-DeSoto International “Safe
Handling Guide” for aerospace coatings and the Material
Safety Data Sheet (MSDS) which provide information on
health, physical and environmental hazards, handling
precautions, and first aid recommendations. An MSDS is
available on request. Avoid overexposure. All mixing and
spraying must be conducted with adequate ventilation and
proper personal protective equipment as recommended.
Obtain medical care in case of extreme overexposure.
For emergency medical information
call 1-800-228-5635.

DeSoto and Desoclean are trademarks of PRC-DeSoto International, Inc., registered with the U.S. Patent Office.

All recommendations, statements, and technical data contained herein are based on tests we believe to be reliable and correct, but
accuracy and completeness of said tests are not guaranteed and are not to be construed as a warranty, either expressed or implied.
User shall rely on his own information and tests to determine suitability of the product for the intended use and assumes all risks and
liability resulting from his use of the product. Seller’s and manufacturer’s sole responsibility shall be to replace that portion of the product
of this manufacturer which proves to be defective. Neither seller nor manufacturer shall be liable to the buyer or any third person for any
injury, loss, or damage directly or indirectly resulting from use of, or inability to use, the product. Recommendations or statements other
than those contained in a written agreement signed by an officer of the manufacturer shall not be binding upon the manufacturer or seller.

Printed in U.S.A. Issued February 1999. Supersedes March 1997.

DeSoto® Aerospace Coatings
PRC-DeSoto International, Inc.
5454 San Fernando Road, PO Box 1800
Glendale, California 91209
(818) 240 2060
Fax (818) 549 7627
www.prc-desoto.com
(Formerly Courtaulds Aerospace, Inc.)