Use rubbing alcohol: Rubbing alcohol can help remove stains from your silicone phone case. Use a cotton ball or cloth to apply rubbing alcohol to the yellowed areas of your case and then simply rub it until the yellow colour fades away.
Clear silicone gets yellowed from exposure to rubber like neoprene wetsuits, some fins, etc. If you're not already, keep your mask away from rubber in storage, ideally in a plastic mask box if you're not already.
To make yellowed plastic look new, clean it with soap and water. Apply a paste of baking soda and water or hydrogen peroxide cream (for UV stains). Leave in sunlight for 4-6 hours, then rinse. Polish with plastic restorer or car polish for a glossy, like-new finish.
Place the plastic pieces under the sun and leave them there for at least a day. It's the UV rays from the sun that in combination with the hydrogen peroxyde will make yellowed plastic white again.
To remove the residue, soak the silicone pieces in distilled white vinegar for about 30 minutes. The vinegar will cut through the mineral deposits. Rinse the pieces well and dry them with a microfiber cloth.
In a small basin that can fit all the silicone rubber items you'll need to clean, pour hydrogen peroxide enough to cover the stained items. Let them soak overnight. The next day, remove the items and rinse them with clean water. You can also opt to double-clean them with a soap dish and a sponge before rinsing.
“Good news is that this yellowing is temporary and it can be removed with normal household cleaning products, simply spraying some household bleach onto the silicone and allowing it to sit for 10-15 minutes before rinsing it off should get rid of the yellow color.”
Most clear phone cases are silicone, a polymer that can is affordable to produce and provides excellent flexibility. Unfortunately, the downside of silicone is that it naturally turns yellow with age. Excessive exposure to certain chemicals, light, and heat can speed up discoloration.
Then create a mild soap solution — dish soap diluted in warm water works well — and use a sponge or rag to gently scrub the rubber. Be sure to thoroughly rinse off any soap residue. For tough stains, a paste of baking soda and water can help lift discoloration. Allow the rubber to air dry.
The best cleaning solution for your silicone phone case is warm soapy water. Add dish washing liquid to a cup of water while it is still warm to ensure that the soap dissolves in it properly. Stir the mixture until it is slightly foamy. Dip a clean toothbrush in the soapy water and scrub your case.
Soak the case for a few minutes in a bowl of warm water, 1 teaspoon of bleach, and 1 squirt dish soap (bleach damages silicone, so only use a little bit).
Things you might try: Easiest - Whatever multi-surface cleaner you have on hand, maybe you'll get lucky. Medium effort - paint w white nail polish or some acrylic from a hobby store. Maximum effort - Wet sanding with 1000 grit to (maybe hopefully) remove the surface yellow, then 1500, 2000, and polish to restore shine.
Some silicones, especially in construction sites, have showed a tendency to turn yellow even before the job has been handed over to the owners. This is directly related to the technology used in neutral cure silicones. All neutral cure silicones will yellow due to oxidation of one of the raw materials.
Method 1: Using baking soda and vinegar
An excellent combination for cleaning yellowed rubber is Arm & Hammer baking soda and vinegar, substances renowned for their cleaning properties. Make a paste by mixing one part baking soda with two parts vinegar in a bowl.
You need to sprinkle a small amount of baking soda on the case. Using a wet toothbrush, scrub the exterior and interior gently. Once done, rinse the case and dry it with a soft cloth. Let it aid dry before using it on your phone.
Soak in Rubbing Alcohol
Pour rubbing (isopropyl) alcohol into the plastic container, filling it until all of the yellowed area is covered. Let it work for about 10 to 15 minutes. Pour out the alcohol and wash the container in hot, soapy water.
Create a whitening paste by mixing equal portions of white vinegar, baking soda, and hot water. Use a toothbrush to apply the paste onto the sole area of your shoe. Let the paste sit for about an hour, then use the toothbrush to scrub the paste off. Rinse the soles under cold, running water.
A translucent molding from an inherently transparent plastics material can be made by incorporating a small amount of mineral filler like talc or silica in it. If we are talking about making a transparent molded article or sheet translucent, it can be done by roughening up its surface using a fine sand paper.
Scrub yellowed plastic with distilled white vinegar.
Then, soak a soft cloth or sponge in the vinegar and wipe the yellowed areas of your appliance with gentle pressure. Let the vinegar sit for a moment, then wipe the area clean with a damp cloth. The acetic acid in vinegar makes it an effective cleaning solution.
How to Remove Shallow Scratches? Clean the plastic surface with a damp cloth, rubbing in a circular motion around the scratch. Dry the area to remove any dirt which should make the process easier to carry out. Apply a mild abrasive, such as toothpaste, furniture polish, baking soda or plastic polish to the scratch.