3M™ 431 and 439 Aluminum Foil Tapes

3M™ Aluminum Foil Tapes 431 and 439 (linered version of 431) are high-performance foil tapes engineered for sealing, masking, shielding, and moisture barrier applications in industrial, aerospace, and electronics settings. These tapes offer strong adhesion, excellent conformability, and long-term durability under a range of environmental and thermal conditions. All three tapes are UL 723 classified and provide excellent resistance to heat, light, moisture, and weathering. The linered versions (431L, and 439L) are ideal for die-cutting or roll-fed applications where clean release and handling are critical.

Applications include: Heat and light reflectivity, sealing and patching in HVAC systems, EMI/RFI shielding, masking in chemical processes, and moisture barrier protection.