A new “green” exterior aircraft painting system has shown corrosion resistance comparable to processes using chromated pretreatment and primers.
new “green” exterior aircraft painting system in development by PPG Industries’
aerospace coatings business has shown corrosion resistance comparable to
processes using chromated pretreatment and primers as well as easier
application than for alternative environmentally responsible
The PPG Aerospace chromate-free depaint/repaint process includes a new exterior
epoxy primer based on nanotechnology and an adhesion promoter PPG manufactures
under license from Boeing, according to Alan Schoeder, PPG Aerospace commercial
coatings global segment manager.
“In salt spray and filiform corrosion testing, metal
surfaces protected by new Desoprime HS CA 7502 high-solids exterior
epoxy primer showed the same corrosion resistance as those coated with
chromated primers,” Schoeder said. The PPG Aerospace environmentally
responsible primer is expected to be qualified this year at Boeing, he
Promoter (EAP-9) uses Boeing’s proven Boegel technology that PPG has licensed,
Schoeder said, enabling PPG to offer airframe manufacturers and third-party
painters an easy-to-use, competitively-priced conversion
“EAP-9 is applied to the stripped aluminum airframe and allowed to dry, and
then Desoprime HS CA 7502 primer is applied,” Schoeder said. “With a
chromated process, the chemical has to be rinsed off, putting hazardous
material into the rinse water. Unlike another chromate-free conversion coating,
only one application is needed with EAP-9, and no mechanical abrading is
When EAP-9 is used with Eldorado corrosion remover and brightener EAC-8,
resulting metal-corrosion resistance is similar to resistance achieved through
processes using chromated chemicals, Schoeder said.
“PPG Aerospace will be offering a complete, easy-to-apply, green
depaint/repaint coatings system that meets the rigors of the exterior aerospace
environment,” Schoeder said.