Photodegradation

Once you go yellow, you never go back.

Guess what mode this toy was left in!

Photodegradation, more commonly referred to by toy collectors as "yellowing," is the phenomenon by which the plastics of which a Transformers toy is made discolor over time. The process is generally started by exposure to ultraviolet light [1], whether from natural sunlight or fluorescent lighting. Photodegradation is most noticeable on figures with bright white or light grey plastics, although it actually happens to virtually all colors (surprisingly enough, when blue plastics photodegrade, it is often referred to as "greening").

There is no hard and fast way to determine which individual figures will be more susceptible to it. A Jetfire opened once, then left in a closet for 20 years seems just as likely to be affected as one left sitting on a shelf for the same amount of time. Furthermore, different pieces of identically-colored plastic on the same toy can photodegrade differently, resulting in a Nightbeat with a normally colored canopy and discolored legs. Even more significantly, areas covered by decals are usually unaffected by the process.

Photodegradation is not to be confused with cigarette smoke residue, which also leaves a yellowish cast on plastic (and can be removed with toothpaste or other products designed to remove cigarette stains) or sun damage, a bleaching effect caused by exposure to direct sunlight (which more commonly affects packaging materials).

Treatment Options

The Transformers fandom has struggled with this issue for ages, and despite having the answer for some time, fans still often tinker with various concoctions hoping to reverse this scourge. Simply put, if a liberal amount of denture cream/household cleanser/virgin blood gets the toy white again, it wasn't photodegradation, it was your common everyday grime that you removed. Some people have experimented with physically removing layers of plastic from toys (via fine-grit sandpaper) to remove photodegradation, but this seems like a temporary fix at best (and one that actually may damage the toy more).

However, a much more promising technique surfaced on discussion boards in December 2008. This newly-discovered method consists of immersing the yellowed figures in a clear container (plastic or glass) full of a hydrogen peroxide solution, then leaving it exposed to direct sunlight for varying lengths of time. Test runs have indeed shown that figures displaying substantial photodegradation were largely or entirely restored to their original pigments. Though the technique has not yet been evaluated by professional chemists, the Decepticons are already plotting to steal the miracle cure for themselves.

Note that even these dramatic results are likely more of a treatment than a cure: the toys are still made of plastic and are still exposed to oxygen and light, so it is reasonable to expect the discoloration effects to return... someday.

A few caveats

• As of August 2009, there have been no reports that the hydrogen peroxide technique causes embrittlement or any other collateral damage to the toys. Some practitioners cite results going back six months. However, there have been no professional long-term tests of this method, certainly nothing approximating a multi-year investigation. Furthermore, no one has been doing this long enough to see if a re-application, years down the line when the discoloration effects have returned, will be as effective or potentially more destructive. The TFWiki will not be held responsible for any damage your toys may incur from trying this new technique.
• Strong solutions of hydrogen peroxide are very nasty business, requiring proper safety precautions: thick gloves, goggles, and ample ventilation. The TFWiki will not be held responsible if you turbo-revvin' young punks mishandle the stuff and require hospitalization and skin grafts.
• It has not yet been determined whether the procedure requires only natural sunlight or if it can be duplicated with a UV lamp. The TFWiki will not be held responsible if you run out and buy a UV lamp only to find out later it was unnecessary. But, uhh, that's really less important.

Fiction

Ask Vector Prime

The S.T.A.R.S. weaponized Gold Plastic Syndrome and invented the Photo Degredation Protocol in a failed attempt to fight off Galvatron's mindless hordes of Decepto-Pack-enhanced human slaves. Ask Vector Prime

External links

• Safety data for hydrogen peroxide, 20%-40%
• Peroxide whitening guide at JoeCustoms