[fuzzythinker]

I use thin 2" tape to wrap the corners and the oldest one is probably 10 years old and no yellowing.

[jamesfinlayson]

Might depend on the age and or brand of the tape - I've seen old tape (30+ years maybe) that has yellowed. I have a 15 years old book at home with some tape and it's okay, except for the tape that wasn't in contact with the book (which is yellowed).