Hi, While 'Retr0Brite', i.e. using hydrogen peroxide to whiten plastic is a bleaching process other types of bleach do not work the same. Bleaching agents, hydrogen peroxide, chlorine bleach, etc. do not work exactly the same so can't be interchanged for this use case.
If you want to learn all about the process from where the color comes from to why the bleaching process works I did a video about that: https://youtu.be/YPl356YKcVs . In the video description is a link to a folder which has a paper that goes along with the video and other resources. Someone has already mentioned obtaining hydrogen peroxide in the form of hair developer. Indeed, this is usually the least expensive source. You can also use sodium percarbonate which comes as a powder (it is hydrogen peroxide and soda ash). Mix the sodium percarbonate with hot water to dissolve it. The drawback is the soda ash is alkaline and may corrode any bits of metal given enough time. You can also use 'SunBriting' which is plain old fashioned sun bleaching. Lots of details in the video and paper. Jeff Birt -----Original Message----- From: M100 <[email protected]> On Behalf Of Jamil Alioui Sent: Thursday, October 21, 2021 2:37 AM To: [email protected] Subject: [M100] Bleaching of yellowed plastic Hello to all of you, I have a small practical question, which will be my first on this list. I quickly looked in the archives but found nothing about this. I hope to knock on the right door. What is the best method to whiten the yellowed plastic of a Model 100 without damaging the screen or sanding (=smoothing) the relief or erasing the inscriptions? I found several possibilities on the internet. One of them is to rub the material with a baking soda paste. But the one time I tried this, the matte plastic turned shiny. I considered dipping the case and keyboard keys in household vinegar, but wanted to make sure it wouldn't affect anything else. I also imagined bathing the yellowed parts in hydrogen peroxide, but this product is very expensive in Switzerland. Thanks in advance; kind regards, Jamil Alioui (Lausanne, Switzerland)
