Hi Stu.
Could be a variery of reasons. Have you had it somewhere hot or humid? Have you cleaned it with anything lately that you havent used before? Like anything there is a reaction for a reason. You need to stabilise it first. Make sure its not in sunlight or a really bright room. Whatever is happening needs to be neutralised. Without seeing a pic I cant offer more mate.

Pic sent to your email mate will take more tonight. Not cleaned it just move it from one room to another that's when I noticed it. Could be light would make a little bit of sence. Being hung on a outside wall instead of a internal plasterboard wall wouldn't cause it. Not damp though 

 

cheers

has it been varnished at all?

not that i know of and defo doesn't look like it, the litho is bubbling in places and doing my head in. i tok it off the wall 6 weeks ago or more and brushed my hand across to see if it was dusty and thats when i noticed litho flakes on my fingers.

Now when you turn the sign into light you can see bubbling

HELP

When the batch of these were originally found there were two distinct versions...both identical...the difference being some were lacquered ,the others plain metallic finish...cannot imagine any problems with the lacquered examples but the unprotected ones would be prone to reaction from any airborn chemical based products..ie household sprays bug sprays etc..it wouldn't have to be a recent contact,,it would work up over time...the other possibility is that you may have one that has since been varnished...I knew someone that I sold a couple to and he varnished them...that was ages ago but if they were not properly cleaned before varnishing,in time they would react...as per Jez comment,the sign needs to be neutralized before it gets any worse but if the problem is under the lacquer then you are stuffed....

Thanks for the comments. Feel stuffed at the moment on what to do. Will try get pics on here tomorrow. But I can't run or polish the sign in any way as contact with the flakes just results in them coming off and leave tiny gold marks ie the plain tin aign