PPG DesoGel EAP-9 Clear BMS 10-128 Conversion Coating and Adhesion Promoter – Gallon Kit

PPG Aerospace DesoGel EAP-9 is a clear, single-product conversion coating and adhesion promoter qualified to Boeing Material Specification BMS 10-128 Type I, Class A — combining the corrosion-inhibiting conversion coating function and the adhesion-promoting function in one application step, streamlining the aluminum surface preparation process before aerospace primer application. Traditional aerospace painting systems require separate conversion coating and wash primer operations — DesoGel EAP-9’s combined function reduces the number of surface preparation steps and associated processing time in the paint shop.

BMS 10-128 is Boeing’s specification for conversion coatings and adhesion promoters applied to aluminum before epoxy primer in commercial aircraft maintenance and production painting. The EAP-9 formulation provides the corrosion-inhibiting chemical film on aluminum that is critical for long-term corrosion protection under the primer and topcoat system, while simultaneously providing chemical bonding sites that improve primer adhesion and peel resistance compared to uncoated or conversion-coated-only surfaces.

The gallon kit provides production-scale supply for paint shop surface preparation operations, with sufficient material for treating large aluminum surface areas in preparation for primer application during scheduled maintenance painting events or production painting operations.

Technical Information

PPG DesoGel EAP-9 combines chromate conversion coating chemistry with organofunctional silane or other adhesion promoter chemistry in a single stable product. The conversion coating component reacts with the aluminum surface oxide to form the chromate-aluminum oxide chemical film that provides active corrosion inhibition through chromate ion release. Simultaneously, the adhesion promoter component deposits functional groups on the treated surface that bond chemically to both the aluminum conversion coating and the incoming primer molecule, creating a chemical bridge that improves primer adhesion beyond what conversion coating alone provides.

The clear appearance of DesoGel EAP-9 distinguishes it from the iridescent yellow-gold color typical of conventional chromate conversion coatings — the clear film makes visual confirmation of application more challenging, requiring careful process control and surface wetness inspection during application to ensure full surface coverage before the product dries.

Application procedure, wet contact time, and rinse or no-rinse requirements must follow the PPG DesoGel EAP-9 product data sheet and the applicable Boeing painting specification. Correct contact time is critical — insufficient time produces inadequate conversion coating and adhesion promotion; excessive time can produce coating quality issues on some aluminum alloys.

Why Choose PPG DesoGel EAP-9?

• ✅ BMS 10-128 Qualified — Boeing approved conversion coating and adhesion promoter
• ✅ Combined Function — One product for conversion coating and adhesion promotion
• ✅ Streamlined Process — Fewer surface preparation steps before priming
• ✅ Gallon Production Kit — Volume for paint shop surface preparation
• ✅ PPG DeSoto Aerospace Quality — Leading aerospace coating preparation chemistry

Applications

DesoGel EAP-9 is used for surface preparation of Boeing commercial aircraft aluminum structure before epoxy primer application, in production painting and MRO maintenance events requiring BMS 10-128 qualified conversion coating and adhesion promotion.

Frequently Asked Questions

Q: What is PPG DesoGel EAP-9?
A: EAP-9 is a BMS 10-128 qualified clear conversion coating and adhesion promoter for aerospace aluminum — combining corrosion-inhibiting chemical film and primer adhesion promotion in a single surface preparation product.

Q: MPN for DesoGel EAP-9 gallon?
A: MPN is EDEAP-9XX8BMG22K.

Q: What is BMS 10-128?
A: BMS 10-128 is Boeing’s material specification for conversion coatings and adhesion promoters applied to aluminum before epoxy primer in commercial aircraft painting systems.

Q: How is DesoGel EAP-9 different from conventional chromate conversion coating?
A: EAP-9 combines conversion coating and adhesion promotion in one product — reducing process steps. Conventional chromate conversion coating provides corrosion protection but requires a separate adhesion promoter or wash primer for optimal primer adhesion.

Q: What primer is applied over DesoGel EAP-9?
A: BMS 10-11AC qualified corrosion-inhibiting epoxy primers (such as PPG Deft 9N-060) are applied over EAP-9 treated surfaces. Consult the applicable Boeing surface finish specification for the approved primer system.