As an "old-timer" I think this problem will never be solved to everyone's
satisfaction :--). Fingernail polish does pop off after a while but is
readily available, but you better publish in a hurry. Some artists varnishes
& laquers turn yellow or brown in time making numbers difficult to read.
How about the newer compounds like B-72; anyone tried them for stability &
abrasion resistance? Our successors, archaeologists, conservators & museum
people are probably always going to curse us one way or another.
Gene prince