A polymeric or other bonding layer between glass plies that contributes adhesion, fragment retention, optical, acoustic, structural, security, or other specified performance.
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Meaning and boundaries
Interlayers are not interchangeable; chemistry, thickness, adhesion, conditioning, edge exposure, temperature, load duration, and product approval matter.
Why it matters in glass restoration
Heat, solvents, standing water, edge damage, or deep removal near a laminate can affect appearance or performance and warrants conservative limits.