Outdoor plastic chairs offer reasonably priced seating for a porch, balcony, or around a patio table, but when they are white they eventually end up with stains. The top layer of coating eventually wears away, and this allows dirt and other grime to penetrate the plastic. Even when clean, white plastic chairs with stains look ugly, and people avoid sitting on them because they do not realize the stains will not come off on their clothes. Instead of living with stained white plastic chairs or throwing them out, try the following ways to clean them. What do you have to lose but ugly dark stains that make otherwise good chairs look like scrap items that should be disposed of.
Before using any cleaning method on outdoor chairs, try it in an inconspicuous area before attempting to clean an entire piece. Look for signs of finish removal, scratches, and any type of damage before continuing to clean white plastic chairs or any other item. When in doubt, proceed with another option.
Try the Mr. Clean Magic Eraser to Clean White Plastic Chairs
The Mr. Clean Magic Eraser really can perform magic. It can remove stubborn marks that no other cleaner can remove. Try using a Mr. Clean Magic Eraser to clean away stains and discoloration on white plastic chairs. If a Mr. Clean Magic Eraser does not work to remove stains from white plastic chairs, chances are nothing will work.
Use Arm & Hammer Scrub Free to Clean White Plastic Chairs
Another one of the best cleaning agents is Arm & Hammer Scrub Free Bathroom Cleaner. Use it according to product label instructions to remove stains on white plastic chairs. It works very well to cut through soap scum in bathtubs and showers, and it is safe to use on acrylic. As the label states, it has oxy foaming action, and if it can cut through tough soap scum, it can remove stains from white plastic chairs. I used it to remove stains from a white plastic outdoor table, and it turned out looking as good as new. If it worked on my resin table, it will likely work to remove stains on chairs.
Try a Mixture of Bleach and Water to Brighten White Plastic Chairs
Bleach can clean away stains almost instantly, and depending on the source of the stains, bleach is a very good option to clean white plastic chairs. Do not use straight bleach to clean white resin chairs or any other potentially delicate items. Dilute it with 50% water, and apply it directly to the stains on the chairs. Allow it to soak in for several minutes. Scrub away the marks using a bathroom cleaning sponge that is safe for delicate surfaces. Chances are the stains will be gone with very little effort.
Source: Personal Experience Using the Aforementioned Products