Whitening yellowed or discolored white plastic can be achieved through several methods, depending on the severity of the discoloration and the type of plastic. Sunlight and hydrogen peroxide are effective, and in some cases, bleach can be used cautiously.
Effective Whitening Methods
Sunlight and Hydrogen Peroxide
-
Exposure to UV Rays: Place the plastic pieces in direct sunlight for at least a day. The UV rays help break down the discoloration. This method is most effective in conjunction with hydrogen peroxide.
-
Hydrogen Peroxide Treatment: Soaking the plastic in a high-concentration (at least 12%) hydrogen peroxide solution is a common method. Drugstore peroxide (typically 3%) may be too weak. Note that this method's effectiveness depends on the material and the cause of the discoloration.
Bleach (Use with Caution!)
-
Diluted Bleach Solution: Dilute bleach with water according to the manufacturer's instructions. Always test on an inconspicuous area first to avoid damaging the plastic. Bleach is a harsh chemical and should be used only as a last resort.
-
Avoid on Sensitive Plastics: Some plastics are not bleach-resistant. Incorrect use can cause damage or discoloration.
Other Methods
While less effective than UV exposure and peroxide treatments, some sources suggest:
- Cleaning with Soft Scrub: For surface cleaning and removing light grime, a gentle abrasive cleaner like Soft Scrub can help.
- WD-40: WD-40 can remove greasy fingerprints and some light discoloration, but it's not a whitening agent.
- Paint: If other methods fail, repainting the plastic is an option, but this is a more involved process.
Important Considerations
- Plastic Type: The type of plastic affects how it reacts to cleaning agents. Always test any method on a hidden area first.
- Discoloration Source: The cause of the discoloration (e.g., UV exposure, stains) impacts the effectiveness of different cleaning methods.
- Safety Precautions: Always wear appropriate protective gear when using chemicals like bleach or hydrogen peroxide. Ensure proper ventilation when working with these substances.
