Whitening plastic?

[theressa]

Hi folks,

What is a good solution to use to brighten and maybe whiten Launcelots chest armour?
Most of the yellow is the glue seams.

Thanks, Theressa

[ctc]

Hmmmm....

I think if it's the glue, you're boned 'cos the plastic will have changed chemically. I know folks have had some luck with Oxy-Clean, and denture tabs; but I haven't tried either myself.

Don C.

[dr_cyclops]

Could soaking in a peroxide mixture, damage or discolor the plastic?

[rche]

there are a bunch of folks in the vintage computer world brightening up their old cpu cases and such with a peroxide mix. I've been trying it out on various toy plastics with mixed results.

Retr0Bright - home

The basic recipe I have used is about 100ml of grocery store 3% peroxide mixed with 1/2 teaspoon of Oxi clean. This is suspended in a paste of some sort. The quickest paste I have made was by heating up the peroxide with a generous tablespoon of cornstarch until it thickens up. You can keep the paste around for a few days, but don't add the Oxy until you are ready to apply it to the plastic.

Mix the Oxy and the peroxide paste and spread them on the plastic. I put the piece I am working on in a sealed ziplock to retain the moisture, and set it under a UV lamp or bight sunlight for a day.

The chemical reaction that yellows the plastic seems to be due to some of additives stuck in the original plastic mixture. For the cpus, these are flame retardant chemicals. Not sure if that stuff is in toy plastic. Also, not sure if the same reaction with the glue can be reversed this way.

I would not recommend trying this with a valuable or super rare piece as you are subjecting it to UV which, when used with the peroxide, does clear up plastics treated with Bromine as a flame retardant, but may NOT be in the toy you are trying to whiten. In other words, you may do more harm than good by placing the toy in UV light.

Some plastics I have cleaned have whitened up, some look about the same. None have turned more yellow, but that may just take a bit more time since they have only recently been exposed to the UV.

Hope that helps.

btw: the cpu folks are using heavier strength peroxide solutions (10%)that you get from beauty supply places. Hydrogen peroxide in heavy concentrations can cause burns, so please be careful if you are trying this out. Use gloves and wash your hands after touching the paste.

[AAAAA]

what I do is put a peroxide in clear stable cup in ia clear plastic container, burp the container to get most of the air out and place it in sunlight for a couple hours
the item DOES not have to be submerged in liquid ,that slows down the process.
what your trying to do is trading earth atomsphere for Hydrogen /oxgen rich one

[rche]

aaaaa

do you have any before after pics?
What type of items have you been brightening?

thanks

[AAAAA]

aaaaa

do you have any before after pics?
What type of items have you been brightening?

thanks

Hard white plastic works the best
polystyrene plastics

[theressa]

Sad to say, but sunlight is hard to get right now

I'd love to see pics too.

I was reading last night choices from bleach, comet cleanser, toothpaste to anyone maybe using the whitening tooth strips!

I know bleach might work. Highly diluted of course. But do I chance it? it would be a good test, and it couldn't hurt it much more.