To effectively clean a yellow plastic case, you can utilize a hydrogen peroxide solution for deep yellowing, or use common household cleaners for lighter discoloration and general grime. The most effective method for tackling stubborn yellowing involves a hydrogen peroxide and water mixture.
Understanding Why Plastic Cases Turn Yellow
Plastic cases, especially those made from clear TPU (thermoplastic polyurethane), tend to yellow over time due to a combination of factors:
- UV Light Exposure: Prolonged exposure to sunlight's ultraviolet (UV) rays can break down the polymer chains in the plastic, leading to discoloration.
- Oxidation: Air and moisture can react with the plastic, causing an oxidative process that changes its chemical structure and results in a yellow tint.
- Chemical Reactions: Contact with certain chemicals, oils from hands, or even dyes from clothing can accelerate the yellowing process.
Effective Methods for Cleaning Yellowed Plastic Cases
Here are several methods to clean your yellow plastic case, ranging from gentle cleaning to more intensive treatments for deeper yellowing.
1. Hydrogen Peroxide Solution (Recommended for Yellowing)
This method is particularly effective for reversing the yellowing caused by oxidation and UV exposure.
- Preparation: In a small bowl, mix equal parts hydrogen peroxide and water.
- Application: Using a clean toothbrush, apply the solution directly to the yellowed areas of the case. Ensure the entire yellowed surface is thoroughly coated.
- Wait Time: Let the solution sit on the case for approximately 10 minutes.
- Rinsing: After the waiting period, rinse the case thoroughly with warm water.
- Drying: Dry the case completely with a soft cloth or air dry before reattaching it to your device.
2. Baking Soda Paste
Baking soda is a mild abrasive that can help lift surface stains and light yellowing.
- Preparation: Mix a small amount of baking soda with water to form a thick paste.
- Application: Apply the paste to the yellowed areas and gently scrub with a soft brush (like an old toothbrush) or a microfiber cloth.
- Rinsing: Rinse the case thoroughly with water and dry it completely.
3. Isopropyl Alcohol
For surface grime, oils, and some light discoloration, isopropyl alcohol can be effective.
- Application: Dampen a clean microfiber cloth with isopropyl alcohol (70% or higher).
- Wiping: Wipe down the entire plastic case, focusing on stained or yellowed areas.
- Rinsing: Briefly rinse the case with water to remove any alcohol residue, then dry.
4. Dish Soap and Warm Water
For general cleaning and light surface dirt before attempting more intensive methods, dish soap is a safe choice.
- Preparation: Fill a bowl with warm water and add a few drops of mild dish soap.
- Cleaning: Submerge the plastic case in the soapy water or dampen a cloth with the solution and wipe the case.
- Scrubbing: Use a soft brush or cloth to gently scrub the case, focusing on dirty areas.
- Rinsing: Rinse the case thoroughly under clean warm water and dry.
Step-by-Step Guide for Hydrogen Peroxide Treatment
Follow these detailed steps for the best results when using hydrogen peroxide to clean your yellowed plastic case:
- Gather Your Supplies: You will need hydrogen peroxide, water, a small bowl for mixing, and a clean toothbrush.
- Mix the Solution: Pour equal parts hydrogen peroxide and water into the small bowl and stir gently to combine.
- Apply to Yellowed Areas: Dip the toothbrush into the solution and carefully apply it to all the yellowed parts of your plastic case. Ensure even coverage.
- Allow to Soak: Let the solution work its magic for about 10 minutes. During this time, the hydrogen peroxide begins to reverse the oxidation process.
- Rinse Thoroughly: After 10 minutes, hold the case under warm running water and rinse it completely to remove all traces of the solution.
- Dry Completely: Use a soft, clean cloth to dry the case, or allow it to air dry fully before using it again.
Comparison of Cleaning Methods
| Method | Best For | Effectiveness for Yellowing | Application Notes |
|---|---|---|---|
| Hydrogen Peroxide | Deep yellowing, oxidation stains | High | Apply with toothbrush, soak 10 min, rinse warm water. |
| Baking Soda Paste | Light yellowing, surface stains, grime | Moderate | Scrub gently with paste, rinse. |
| Isopropyl Alcohol | Surface oils, light grime, minor discoloration | Low-Moderate | Wipe with cloth, rinse briefly. |
| Dish Soap & Warm Water | General dirt, grime, pre-cleaning | Low | Soak or wipe, scrub gently, rinse. |
Prevention Tips for Plastic Yellowing
While reversing yellowing is possible, preventing it is easier:
- Limit UV Exposure: Keep your plastic case out of direct sunlight for extended periods.
- Regular Cleaning: Clean your case regularly with mild dish soap and water to remove oils and dirt that can contribute to discoloration.
- Avoid Harsh Chemicals: Do not use abrasive cleaners or harsh solvents, as these can damage the plastic and accelerate yellowing.
