Yesterday I opened a letter in a darkened room, and it was one of those envelopes that are self-sealing (No licking the gum). Anyway, as I opened it I noticed the gummed area begin to glow like a little fire was happening along the gummed strip - what was that? was it static or are there chemicals in the gum that really do light up when you unstick the envelope? the firey stuff looked bluish with a white edge
It could be something called triboluminescence. This is generic term for light which is emitted when a material is mechanically excited in some way. The standard lecture example of this is a glow sometimes seen when cutting diamonds. Not sure how it was discovered but you can see it in much less heavy duty examples than diamond cutting I think if you pull sticky tape off something rapidly it can be seen. Certainly that 'glow' you describe is typical of triboluminescence. Im not sure of the exact foundation of triboluminescence. But if memory serves me it seems to have somthng to do with charges being separated when their crystal structure is disturbed, the light I believe is created by the rapid recombination of these charges. Theres also a similar effect called fractoluminescence which I believe is similar in origin, cant remeber the difference. Im sure the net will tell you the difference and indeed if evvelope gum exhibits such behaviour but given sticky tape does it strikes me as very possible.
Wow I like this - so I've seen an effect that hasnt been properly investigated or understood ! No wonder it freaked me out - thanks for the links - bookmarked em
Well I can't be certain, its just my best guess. It could be something as mundane as luminescent gum, though I do like triboluminescence, great word. Look at ti in the dark again, that will tell you if it was casued the mechanical action of opening it or whether it just glows.
Its definitely triboluminescence as far as I can tell I will try it more but I think thats what it was
