Kudos to TI...

[blackjetrock]

(11-29-2023 05:08 AM)Bushcat Wrote:  If this film is Anisolm, it has two apparently contradictory characteristics: on the one hand, its expiry date is 6 or 7 months after manufacture which suggests it ages rapidly. On the other hand, then-Hitachi had a repair note which says that imperfect bonds can be repaired i nthe field by heat and pressure, simply by using something like a broad-head soldering iron and some kind of buffer material to protect whatever substrate you're pressing down on. I've done this successfully with a couple of Casios in the past.

Yes, lot of material has over-enthusiastic expiry dates. For DIY it usually doesn't matter too much.
The repair procedure you describe is one that I have used. I use a wide 40mm or so bit on my temperature controlled iron and some silicon sheet as a buffer. I have improved quite a few heat seals like this, but after 2 or 3 'reworks' improvement tends to stop for me.

Andrew