Datasheet

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3M
™
Extreme Sealing Tape
4411N • 4411G • 4411B • 4412N • 4412G
Creating an
Overlap Joint
It is often required to overlap 3M™ Extreme Sealing Tape onto itself. In this case,
the ionomer backing of the first piece is one of the substrates to which the second
piece of tape is bonding. The tapes should overlap at least 2 cm (3/4 in).
Surface Preparation
The ionomer does not need to be cleaned prior to bonding unless it has been
contaminated with oil, dirt, grease, etc. If the bonding area of the ionomer has been
contaminated, IPA/water can be used to clean the surface.
A quick wipe of AP111 on the ionomer is suggested for best performance of the
overlapping tape. AP111 will approximately double Extreme Sealing Tape’s
adhesion to its own ionomer backing.
Pressure
Firm pressure should be applied to all points of overlap between the two tapes to
join the adhesives and create a robust seal.
Additional Sealing
To increase sealing robustness, a small dab of liquid sealant 3M™ 4000UV is
suggested at the points of overlapping tape. This step maximizes process robustness
by decreasing the chance that an improperly pressurized overlap might leave a gap.
In the above images, the white circles indicate where 3M 4000UV should be applied
in the corner and step situations. These two general categories can describe most
common configurations. For configurations other than these, the general principle is
to use 3M™ 4000UV in any place where water (shown as blue arrows) could seep
past an improperly joined overlap.
Do not apply 3M™ Extreme Sealing Tape over the top of uncured liquid sealants.
If using over a liquid sealant, check with sealant’s manufacturer to determine when
sealant is 100% cured. Certain chemicals produced by the curing process of some
liquid sealants may cause detrimental effects to the long term stability of the bond.