I’m thinking it’s only a slow-decay phosphor if they claim a half-life of 24hrs. Ie, it won’t glow brightly and also fade quickly, but glow dimly but for a much longer time.
Years ago NPR had a story about US Radium in New Jersey, I found a similar story in Wikipedia Radium Girls
How would you think something like a watch dial would have such an impact on someones life.
here is what i know
it is cheap - it cannot be tritium
it does glow all night - maybe it would eventually fade but i have not tried to keep any in the dark for a week to see what it does
when i said it does not need light charging, that was for 12 hours
when i was a kid though, i had an old big ben westclox alarm clock, and you could see sparkles on its glowing hands, if you looked very closely
with good kid eyesight
i was told, maybe this is wrong, that those were gamma rays hitting the phosphor stuff, making it sparkle
i don;t really know
maybe the thing had some radium in the paint, this was the 60s, and it was really radium decay
i assumed when the new tape lasted all night, that it was this gamma hitting phenomenon
now i don;t really know
but i assume radium is also out, due to expense and legalities
maybe i will put some in a dark box for a week and see if that is still visible at night in the complete dark like the 12 hour glow
i will probably find that it does gradually fade out, it just takes more than 12 hours,
there are no gamma ray sparkles, and what i saw before may have been radium paint,
Yes I read the book - it said some of the workers actually glowed in the dark - you could see their skeletons through their skin.
This was before they seemed sick.
The radium glow was thought to be healthy.
There were people who knew that was a lie, the bosses, but they of course didn;t say it.
They at one point told the workers not to ‘point the brushes’ with their lips, and gave them rubber doohickeys to do that with.
But the workers didn’t like those and went back to lips.
The bosses knew all this and didn’t enforce it, since that made the work faster.
The book is just called “Radium Girls”. It’s fairly recent. Great book, terrible story.
Emiriya, welcome to BLF! I’m curious how you found us. Have you been lurking for a while? Surely this thread didn’t pull you in!
The tape is probably just glow-in-the-dark tape. The listing has a lot of dubious claims, some of which seem to contradict each other. But, in the end, it’s probably the same stuff we’re used to seeing. You light it up with some other light source, and it re-radiates that light for some time afterward.