If you have some vintage plastic items that are yellowed with age, they’re not always destined for the curb. Retro-obsessed geeks have created a cheap, homemade solution for restoring old plastic.Manufacturers add various chemicals to the ABS plastic used in most electronics to act as flame retardants. Over time, those chemicals react to the plastic’s basic polymers and turn an ugly yellow colour. Museums and vintage electronics collectors have devised a solution from hard-won restoration efforts to bleach plastics back to their original coloration.
It was originally thought that the yellowing was permanent and that the only solution to this was to paint the plastic in its original colour and cover the problem up. However, a chance discovery was made in March 2008, by The CBM Museum at Wuppertal in Germany that immersing parts in a solution of hydrogen peroxide for a few days could partially reverse the process. This was initially taken up by the Amiga community in Germany and the idea eventually found its way to the English Amiga Board, where a madcap collection of chemists, plastics engineers and retro hackers managed to perfect this concept and put it on steroids, with help from other forums.
And what was the magic bullet? It turns out the perfect plastic bleaching solution is a mixture of hydrogen peroxide, glycerin, oxygen based bleach like OxyClean, and xanthum gum to make it sticky. Brush it on and leave it out in the sun or under a UV lamp to accelerate the process and your Commodore will be sporting a show-room fresh shine in no time. The Retr0Bright site has a few recipes and, for those who paid attention in chemistry, a detailed explanation of the chemistry behind the entire process.