Which type of failure is characterized by pulling the adhesive or sealant loose from the substrate?

• A. Antenna suitability
• B. adhesive failure
• C. Backlite
• D. Bead

Answer: (B)

Adhesive failure happens when the boundary between the adhesive and the surface it’s meant to bond to gives way. If the sealant pulls loose from the substrate, the weak link is at that adhesive–substrate interface, meaning the bond to the surface failed rather than the adhesive tearing apart itself or the substrate cracking. That’s why this describes adhesive failure—the adhesive fails at the interface with the substrate.

Other terms don’t describe the failure mode: antenna suitability is about radio performance, backlite refers to the rear glass component, and bead is just the sealant bead used in installation, not how the bond fails.