Looking for oxidizing color-changing material

[Tommy_P]

Hi,

I wonder if there is a material or paint/dye that would change color when exposed to air? Ideally, it should have the following properties:

White-to-black, black-to-white, or any other high contrast color transition (e.g, yellow-to-brown would work too)
Works under normal conditions
Transition should occur within seconds (e.g., anywhere between 1 and 20 seconds)
Color change is irreversible
Non-toxic
Reasonably cheap

Thank you for any tips!

P.S. As you can probably tell from my question, I'm totally not an expert in materials or chemistry, so please answer in "plain English".

P.P.S. Also, the first thing that comes to mind is how an apple turns brown when one bites off a piece. I think this is kind of the effect I'm looking for.

 

[Tommy_P]

Hi, everybody. So no answers... which means there's no such thing?

Well, is there any other method to achieve a similar color-changing effect? I'm thinking Transitions lenses that react to UV. It is different from what I'm after in several aspects:
1. Doesn't work indoors
2. Reversible and expensive

Any thoughts? Thanks!
Tom

 

[B0b-A]

... is there any other method to achieve a similar color-changing effect? I'm thinking Transitions lenses that react to UV ...

Paint is available which does that ... www.mindsetsonline.co.uk/Catalogue/ProductDetail/photochromic-pigments

 

[Tommy_P]

Thanks, B0b-A! I had a hunch these paints do exist. The only problem, they react to UV, so won't work indoors. Also this will probably work differently on a sunny day vs an overcast day. That's why initially I was hoping to find an oxidizing dye, because the % of oxygen is always about the same everywhere.

 

[B0b-A]

Dulux have "magic" white paint which is pink until it dries white in about an hour ...

https://www.dulux.co.uk/shop/interior-paints/magic-white-silk

Ideal if you want temporary pink graffiti on a white wall

 

[Borek]

Fast reaction (within seconds) can be difficult, but there should be plenty of dyes capable of reacting with air oxygen and substantially changing their color. Trick is - while I am pretty sure they must exist, I have no idea about details.