solution to yellowing

[RichyX]

thouht id post this up as i read a few years ago about a solution to fix yellowing toys

well i had a go this week and these are my results

the solution is hydrogen peroxide, you need the 35% food grade stuff and can be bought off ebay

i used a transformer which i had so thought id give it ago

heres some pics of before and after

all stripped down

once at this stage give each part a clean with some soapy water and tooth brush

also you dont have to take the item completly to bits i left the arms intact

next put in a glass jar and fill with solution

this needs to be put into direct sunlight, and you will start to see air bubbles in the solution, if in direct sunlight for a couple of hours then the process will be quicker, unfortuantly for me i didnt have much sunlight so had to leave it in solution for 4 days

now just be carefull, with coloured plastic as it can be turned white, so you need to keep an eye on it, and also some softer plastics, as the softer plastics on this, mainly joints have blistered so i need to replace these, but the rest are perfectly intact, no softeness in the plastics at all, if you do different colours, use different jars i just tested it all in one jar as it was a junker

[RichyX]

heres the after pics once cleaned with water and assembled

you can see in this pic the blistering on the light grey joints

also a warning, do not get this stuff on your hands, i did and it gave my fingers pins and needles and also turned them white taking the moisture out my fingers, clean off with cold soapy water asap and moisturise your hands if you get any on you

anyway for the sake of £10 its worth givingit ago ona junker and see how you get on, at least there isa way of fixing yellowing toys and i will be doing the same to some of my tfs which have badly yellowed over the years

[nightmareB4macross]

Awesome job. I know what you mean about the plasti becoming white.

I tried this same thing on a dingy and yellowed 1/55 GBP-1S using a over the counter 3% solution, but it took 4 months to actually see results. I kept the parts in the sun for a week and nothing happened. Then, at the second week up until the 4th month, I left the parts in my garage. I did remove all the yellow but turned he blue parts light blue, while the red and white cleaned up really nicely and held their color.

The reason why I left the parts soak for 4-months is that I totally forgot about them. But hey, it still works.

Just a note: remove all metal parts as they will oxidize due to the hydorgen peroxide.

[MechTech]

So what's the BBQ sauce for? Thanks! I've got an old VT-1 I'm thinking of bleaching out. - MT

[gwfalcon]

Many thanks for sharing such a good method, especially with practical example! Will go back to try immediately.

BTW, two small questions:

1. must expose to sunlight? A room with daylight lamp, OK?

2. some part, like the chest of vf-1s (shown below) has other colors, before putting it in the solution, is it necessary to put tape to cover the color part in order to avoid its bleaching?

Thx again for the reply.

Edited November 8, 2009 by gwfalcon

[big F]

There was/is a tread on this very subject here on MW. I amoung others did some quite extensive research on this.

For all who want or need to know you need sunlight as it helps to activate the peroxide and a sealed glass jar is needed. you will maybe need to open it at some point to let out the exess gasses.

It can and will react with metal especially the nickle based plating used in toys. Thats not to say it will be a disaster it can just make it go a bit white or blacken it slightly.

I can mess with stickers but the type that is used on Bandai valks (the clear ones) are ok. Silver foil ones as used by Hasbro also seem to come out ok.

It does work the stronger the solution the faster it will work.

Im blessed with an office window that is south facing and even when its cloudy get goods light.

Now to the bad.....

After doing this to my test subject a Bandai 1/55 made of parts. I put all the parts into storage in a cool room and sealed in a box. Months later the yellowing is starting to come back.

I am fairly sure this is not an isolated case, maybe if Bandai used a slightly different mix to say Hasbtro then you may have better permanant results.

On the really bad Im sure that some are using this to great affect on eBay to hock otherwise near worthless plastics (both toys and other stuff) as minty fresh hardly touched classic collectables.

Be carfull out there.

I have used it on various thing like old classic telephones toys and auto parts. it does work on most of them, blacks and dark colours sometime suffer but all come out better.

Im not saying dont try it. It is great seeing those yellowed crapped out toys comming out all new like. especially as when you first put em in you keep checking every few mins to see is theres a change. Then like in all good things that day you dont look at it at all is when it all changes.

Try it you have nothing to loose. Just a few $/£ etc on cheap Hydroperoxide and a jamjar or preserves jar to put it all in.

Obviously it goes without saying dont dunk your $500 mint in box Valk you got at that comic-con unless you have done some practicing.

One thing I have yet to try is sealing them in clear coat such as plasicote or its U.S version to see what this does to stop the yellow comming back.

Edited November 8, 2009 by big F

[gwfalcon]

Hello Mate:

Thank you again for making up the detailed explanation.

Another small question: After bleach out the yellowished parts, then right after drying them, if we put a top coat properly on them, does it mean that it will never ever becoming yellow again, right (I personall think so cz O2 is completed isolated but not sure).

My first time to feel in deep love of chemistry.

There was/is a tread on this very subject here on MW. I amoung others did some quite extensive research on this.

For all who want or need to know you need sunlight as it helps to activate the peroxide and a sealed glass jar is needed. you will maybe need to open it at some point to let out the exess gasses.

It can and will react with metal especially the nickle based plating used in toys. Thats not to say it will be a disaster it can just make it go a bit white or blacken it slightly.

I can mess with stickers but the type that is used on Bandai valks (the clear ones) are ok. Silver foil ones as used by Hasbro also seem to come out ok.

It does work the stronger the solution the faster it will work.

Im blessed with an office window that is south facing and even when its cloudy get goods light.

Now to the bad.....

After doing this to my test subject a Bandai 1/55 made of parts. I put all the parts into storage in a cool room and sealed in a box. Months later the yellowing is starting to come back.

I am fairly sure this is not an isolated case, maybe if Bandai used a slightly different mix to say Hasbtro then you may have better permanant results.

On the really bad Im sure that some are using this to great affect on eBay to hock otherwise near worthless plastics (both toys and other stuff) as minty fresh hardly touched classic collectables.

Be carfull out there.

I have used it on various thing like old classic telephones toys and auto parts. it does work on most of them, blacks and dark colours sometime suffer but all come out better.

Im not saying dont try it. It is great seeing those yellowed crapped out toys comming out all new like. especially as when you first put em in you keep checking every few mins to see is theres a change. Then like in all good things that day you dont look at it at all is when it all changes.

Try it you have nothing to loose. Just a few $/£ etc on cheap Hydroperoxide and a jamjar or preserves jar to put it all in.

Obviously it goes without saying dont dunk your $500 mint in box Valk you got at that comic-con unless you have done some practicing.

One thing I have yet to try is sealing them in clear coat such as plasicote or its U.S version to see what this does to stop the yellow comming back.

[RichyX]

it does not harm paint so no masking is required, that tf has a painted head and its made it cleaner without damaging the paint

[Vi-RS]

I wonder this is temporarily fix or permanent. The reason I ask is basically I understood that the surface of the plastic that was oxidised has been washed off. Leaving the undernealth virgin plastic so it looks new. I wonder it will speed up the process later on since the surface of the plastic was chemically washed out.

It's pretty much the same thing as automobile plastic headlights's len which turn yellowed over years because the surface was oxidized. Some people do water sanding and it turns out great, but it comes back 3 or 6 months later on and faster than before. Brand new headlights is coated with protective coat to prevent that so basically we are removing the yellowing protective coat. This is also why brand new vehicle will have rainbow effect surface and those are the protecitve coat.

[BlueMax]

I have tried the peroxide treatment and for a while i was elated by the results.

The V1 Yamato 1/60 Hikaru VF-1A i tested on , turned yellow again about less than 2 months after treatment. I really wonder if a top coat would have helped matters....

But the point is, this might not be a permanent solution to the yellowed toys.

Also,I swear that the diecast like those used in the Yamto V.1s' legs and chest assembly and can possibly weaken the toy after prolonged exposure to peroxide.

[thegunny]

Here's a link to a site that may be able answer a few of the questions asked.

Retr0Bright

[RichyX]

I wonder this is temporarily fix or permanent. The reason I ask is basically I understood that the surface of the plastic that was oxidised has been washed off. Leaving the undernealth virgin plastic so it looks new. I wonder it will speed up the process later on since the surface of the plastic was chemically washed out.

It's pretty much the same thing as automobile plastic headlights's len which turn yellowed over years because the surface was oxidized. Some people do water sanding and it turns out great, but it comes back 3 or 6 months later on and faster than before. Brand new headlights is coated with protective coat to prevent that so basically we are removing the yellowing protective coat. This is also why brand new vehicle will have rainbow effect surface and those are the protecitve coat.

the only reason the headlights turned yellow is the manufacturers used yellow headlamp bulbs instead of white

ive never seen a headlamp go yellow when usinga white or blue bulb, but ford had this problem on the mondeos (contours) as they used yellow bulbs and over the years turned the light lenses yellow

[Vi-RS]

the only reason the headlights turned yellow is the manufacturers used yellow headlamp bulbs instead of white

ive never seen a headlamp go yellow when usinga white or blue bulb, but ford had this problem on the mondeos (contours) as they used yellow bulbs and over the years turned the light lenses yellow

I doubt that, headlights turns yellowing or foggy starting from the top especially those new car that has large surface facing up. If yellow bulbs cause that then the yellowing will start from the front of headlight but not starting from where the surface facing up.

Anyway, my question is how the thing works and will it last?

[big F]

It is quite posible that coating the freshly peroxided plastic with Krylon or Plasticote clear may shield it from the air which may stop or really slow it down.

This is how ever totally useless if you have anything that is really worth money though but fine for customs.

[hirohawa]

Great thread. very informative

Thanks

[eugimon]

I asked my wife about this (materials engineer) and this is what she said: So hydrogen peroxide works by releasing the unstable oxygen which binds to organic compounds and destroying them.

The reason why you leave the jar out in the sun is that the UV injects energy into the solution helping to free the oxygen and turned the hydrogen peroxide into water + oxygen.

What you're seeing is two things:

one: a lot of the dyes used in plastics have some organic compounds, they're being destroyed to expose a "fresh" layer.

two: The plastic itself is being damaged by the oxidation process and new microscopic pits are being formed.

So if you don't seal the plastic, it now has more surface area that can react to oxygen. Lots of plastic have an anti-UV compound mixed in to protect against yellowing, these are probably damaged as well and thus, yellowing will probably be accelerated on the newly cleaned toy.

[BlueMax]

I asked my wife about this (materials engineer) and this is what she said: So hydrogen peroxide works by releasing the unstable oxygen which binds to organic compounds and destroying them.

The reason why you leave the jar out in the sun is that the UV injects energy into the solution helping to free the oxygen and turned the hydrogen peroxide into water + oxygen.

What you're seeing is two things:

one: a lot of the dyes used in plastics have some organic compounds, they're being destroyed to expose a "fresh" layer.

two: The plastic itself is being damaged by the oxidation process and new microscopic pits are being formed.

So if you don't seal the plastic, it now has more surface area that can react to oxygen. Lots of plastic have an anti-UV compound mixed in to protect against yellowing, these are probably damaged as well and thus, yellowing will probably be accelerated on the newly cleaned toy.

Thanks! now I know why mine become even more yellow after one run of treatment. think I'll try another time, but this time, Krylon anti UV will be my friend right after that.

[Vi-RS]

I asked my wife about this (materials engineer) and this is what she said: So hydrogen peroxide works by releasing the unstable oxygen which binds to organic compounds and destroying them.

The reason why you leave the jar out in the sun is that the UV injects energy into the solution helping to free the oxygen and turned the hydrogen peroxide into water + oxygen.

What you're seeing is two things:

one: a lot of the dyes used in plastics have some organic compounds, they're being destroyed to expose a "fresh" layer.

two: The plastic itself is being damaged by the oxidation process and new microscopic pits are being formed.

So if you don't seal the plastic, it now has more surface area that can react to oxygen. Lots of plastic have an anti-UV compound mixed in to protect against yellowing, these are probably damaged as well and thus, yellowing will probably be accelerated on the newly cleaned toy.

That's exactly what I expected, it's temporarily fix like cleaning automobile headlights unless you apply a protective coat to shield it.

[mrclean08]

I asked my wife about this (materials engineer) and this is what she said: So hydrogen peroxide works by releasing the unstable oxygen which binds to organic compounds and destroying them.

The reason why you leave the jar out in the sun is that the UV injects energy into the solution helping to free the oxygen and turned the hydrogen peroxide into water + oxygen.

What you're seeing is two things:

one: a lot of the dyes used in plastics have some organic compounds, they're being destroyed to expose a "fresh" layer.

two: The plastic itself is being damaged by the oxidation process and new microscopic pits are being formed.

So if you don't seal the plastic, it now has more surface area that can react to oxygen. Lots of plastic have an anti-UV compound mixed in to protect against yellowing, these are probably damaged as well and thus, yellowing will probably be accelerated on the newly cleaned toy.

What would be the recommended item to seal the plastic with?

[leading edge]

What would be the recommended item to seal the plastic with?

Most toys during the 80' were made sometimes without a UV blocker added to the plastic to retard yellowing caused from either aging via sunlight or chemical stains. I would suggest to prevent yellowing in the first place try a light coat of airbrushed UV protective acrylic or a special case designed to block UV rays both can be found at either a hobby store or art supplier ( i.e. Aaron Brothers and Hobby People). I usually coat some of my models this way as a final touch to prevent scratches to the paint job.

[bluemax151]

A buddy linked me this pretty good thread on the subject a long time ago.

http://www.thetf.net/forum_posts-TID-13204-PN-1.htm

People have been using this for Legos (where it's pretty necessary) for a while too.

[MechTech]

Has anyone tried this http://www.permalac.com/?gclid=CIfC7P3J-Z4CFQWTzAod92euMw or another product? There's clear sealants out there that are UV proof. I've got toys that are over 30 years old with no yellowing, then I have some that are horribly yellowed including legos.

I'm thinking our white finished models could benefit from this too. My testors painted white parts yellowed bad - in the storage box! - MT

[leading edge]

Has anyone tried this http://www.permalac.com/?gclid=CIfC7P3J-Z4CFQWTzAod92euMw or another product? There's clear sealants out there that are UV proof. I've got toys that are over 30 years old with no yellowing, then I have some that are horribly yellowed including legos.

I'm thinking our white finished models could benefit from this too. My testors painted white parts yellowed bad - in the storage box! - MT

A UV blocker can be used if you can get the paint to work with it. I myself have yet to try this but some classmates of mind like to mix a UV retarder into their paint for some painting they do if the haven"t enough money to afford a uv reflective glass. I would have to ask them or read up on the subject to comment further.