Heat Shrink Sleeves with Green Paint

     Once upon a time, before Raychem heat shrink sleeves developed to using the PCI (permanent change indicator as seen here), they utilized a different inspection tool.  At that time; the heat shrink sleeve backing was sprayed with a green thermochromic paint.  This green paint would burn off / turn black as the proper amount of heat was applied to it leaving the backing looking something like this:

An example of the thermochromic paint installed on Raychem shrink sleeves used up through the early 1990's

     This was a fantastic system and it worked very well for a number of years.  One annoyance of this paint was that it would sometimes flake off of the backing in small amounts; so if you were working with it all day cutting, bonding, rolling, packaging; you would ultimately be covered in a light dusting of green paint.  I know this because I worked with this material all through the summer of 1989 (my senior year of high school) and beyond! 

     So, while this green paint is no longer used by what is now Covalence (formerly known as Raychem shrink sleeves), the 'meat and potatoes' of the product still remain the same; whether that is the radiation crosslinked backing or the adhesive sealant.