From Wikipedia, the free encyclopedia
Jump to: navigation, search
This TRS-80 Color Computer 2 case shows significant yellowing.
After treatment, the yellowing is largely reversed.

Retr0bright is a public domain[1] chemical mixture used to remove yellowing from ABS plastic computer and electronics cases, including computers that were manufactured by Commodore and Apple in the 1980s and 1990s, and various video game consoles and cartridges.[1] Yellowing is caused by both bromine and exposure to UV light. Bromine is added[clarification needed] to ABS plastic, acting as a fire retardant.

Retr0bright is hydrogen peroxide, a small amount of an "active oxygen" laundry booster TAED as a catalyst, and a UV lamp. Sunlight can be used instead of a UV lamp.[2]

The optimum mixture and conditions for reversing yellowing of plastics:

  1. Hydrogen peroxide solution, the stronger the better. 12% works fine; 6% works also, just more slowly.
  2. UV light, either from sunlight or a UV lamp.
  3. Approximately 1/4 teaspoonful (4.9 ml) per gallon (3.8 l) (1/3072) of Tetraacetylethylenediamine (TAED)-based laundry booster (concentrations of TAED vary).

Xanthan gum or arrowroot can be added to the mixture, creating an easier-to-apply gel.[3]

When making and applying the mixture, users are advised take proper safety precautions and wear protective gloves and goggles. Hydrogen peroxide can cause serious chemical burns and blindness if splashed in the eyes.


  1. ^ a b - The “Retr0bright” Project
  2. ^
  3. ^ - Making the Retr0bright Gel

External links[edit]