I have tried a similar process on some very yellowed air vents, I filled a laundry tub with 50% bleach and 50% water, after soaking for a full day the plastic is still a bit yellow but only half as bad as before. Do you recommend trying to let it soak a few more times? I think the problem may be the lack of sunlight in the laundry.
Hi Ben, thank you for your message. Light is an important ingredient for the process, so a transparent container is recommended.
If you are going to give it another turn, please was the parts well. The detergent forms a residue on the plastic and it builds up after each soak. And the more it builds up, the harder it is to remove.
Hi Tania, not sure what a Marybelle telephone is and what it is made of.
If you want to do something about the discolouration properly, you will need to take it apart. I any case you will need to wash the parts of the body shell.
I do not know what material your phone is made of. Bakelite? Plastic? Marble?
I made good experiences with hair salon Peroxide creme for bleaching. I used a small paint brush to apply the creme to the yellowed parts. It’s a white Italian “Grillo” phone which wasn’t too bad, but still yellowed. I presume it is ABS plastic. The creme I used was 6% Peroxide and available online. In the local drugstore I only found expensive dyeing kits, the peroxide creme itself is cheap. Stronger stuff bis also available.
Once applied, I put the parts into a freezer bag and into the direct sunlight.
I also tried just brushing on some creme and not using a bag. The creme dried up, but still worked! It could be cleaned off with a damp cloth later. This way it would not be required to disassemble a phone completely. But I would still not recommend to use it around an assembled keyboard etc.!
No warranties given whatsoever 😉 better try carefully.
Best regards, Dietrich
Hi Jens, thank you for your message. I wore glasses and used gloves when preparing the mixture. During the process I did not use gloves, but did wash my hands thoroughly afterwards. After all the product I used was made for handwashing laundry.
I disposed of the liquid by pouring it through the sink.
Hello Arwin, I tried Vanish Oxy Action from Rossmann. I bleached a TN E2 housing (pastel green) with some shadows probably caused by stickers. I removed the steel clamps and put the housing and receiver in hot water with cleaner about four hours with sunhine in a transparent box. I was a little bit shocked that the green went nearly white and after washing and rubbing with a microfaber cloth (no extra cleaner or polish) the green slightly showed up again a little bit. The result is much too bright in comparison to my other TN E2 housings. The brass tread does not care about oxy activation and looks fine. Probably I overacted with heat, sun and cleaner. But I works fine and the dose is the poison.
Hi Henning, thank you for your message. I did some further experiments the last few weeks. I really need to update my article with the new things I learned.
Oxy action products are not good for metal parts. I tried some peroxide solution too, instead of the oxy action product. That worked better and faster.
I used it on a bright yellow housing. I had the impression that it got lighter than it should. It seems that bleaching is good for grey, white and beige (and similar colours) but is somewhat dangerous for brighter colours.
I am not sure what is the best course of action for brighter colours. High dosage and short time or low dosage and very slowly. I think the latter. I need to find a piece of plastic that had a bright colour but is now yellowed to do a good experiment.
very interesting article!
I was wondering if the body shell started to yellow again after some time?
The degradation reaction of ABS cannot be stopped, if I understood the chemistry well..
Could you compare the result after a couple of months/year(s)?
Thank you for sharing your experience! I want to try it on some old retro console of mine!
Hi Kristof, I have not noticed any new yellowing again. But I keep my plastic phones well away from direct sunlight.
I think it very much depends on the composition of the plastic and the quality. To say something really meaningful about this, I would have to do a longer term controlled experiment, but I do not have the time to do that right now.
I do have some new experiences with bleaching, so I will update this article.
Have you seen 8-bit guy on youtube? He has some great videos about bleaching old computers.
We’ve just bought a motorhome with yellow walls and are planing on cleaning them with Hydrogen peroxide, but obviously won’t be able to use sunlight as I’ve light. Does anyone have any idea what watts to use for the UV light?