<p>I'd try <strong>polyurethane</strong> varnishes.<br />
They are weatherproof, contrary to standard acrylic varnishes, they are transparent, but may absorb a bit of UV light, as UV is sometimes a catalyst to the reaction to form them (<a href="https://en.wikipedia.org/wiki/Polyurethane" rel="nofollow noreferrer">source : wikipedia</a>) (only a guess here, as I didn't find valuable PU absorption spectrum). It is also stated that polyurethanes with <strong>isocyanates</strong> react with UV light and it discolours them over time, so if you can, try isocyanate-free polyurethane.<br />
Anyway, it is a very common outer coating protection for wood, so it is not very expensive (found some at 20 €/$ for 250ml).<br />
You could give it a try and see how it works for you.</p>

CC BY-SA 4.0
2021-08-30T12:15:24.847Z
2021-08-30T12:46:05.837Z
2021-08-30T12:46:05.837Z
Osamoele
<p>I have luminous powders from ebay, those containing europium and glowing in various colors in the dark after being charged with visible or ultraviolet light. I would like to make them into paint by mixing them with a suitable paint base. I have seen luminous paint base offered for sale but at extravagant prices. Is there a more affordable and general solution? I think the main requirement is that the paint base should be weatherproof (if for use outdoors) and that it not absorb long-wave ultraviolet light (315-400mn), as this wavelength given off by the sun helps recharge the luminous pigment.</p>
<p>Edit: After looking more into this, I realized that fluorescent paint should have the same requirement as luminous paint, as both need exposure to long-wave UV. <a href="https://www.fxsupply.com/uv/uvpaint.html" rel="nofollow noreferrer">This site</a> sells fluorescent paint that has an acrylic base. So a possible paint base is <a href="https://en.wikipedia.org/wiki/Polyvinyl_acetate" rel="nofollow noreferrer">polyvinyl alcohol</a> (white glue), though it may not be weather resistant. <a href="https://en.wikipedia.org/wiki/Shrinky_Dinks" rel="nofollow noreferrer">Shrinky Dinks</a>, made of polystyrene, came in a variety impregnated with luminous zinc sulfide. So protecting a luminous painted surface with a layer of plastic should work.</p>

<material-selection><paint>
What is the best base to use for luminous paint?
Chris Jenks
# What is the best base to use for luminous paint?

(Asked by: username_0 on 2021-08-30)

I have luminous powders from ebay, those containing europium and glowing in various colors in the dark after being charged with visible or ultraviolet light. I would like to make them into paint by mixing them with a suitable paint base. I have seen luminous paint base offered for sale but at extravagant prices. Is there a more affordable and general solution? I think the main requirement is that the paint base should be weatherproof (if for use outdoors) and that it not absorb long-wave ultraviolet light (315-400mn), as this wavelength given off by the sun helps recharge the luminous pigment.

Edit: After looking more into this, I realized that fluorescent paint should have the same requirement as luminous paint, as both need exposure to long-wave UV. [This site](https://www.fxsupply.com/uv/uvpaint.html) sells fluorescent paint that has an acrylic base. So a possible paint base is [polyvinyl alcohol](https://en.wikipedia.org/wiki/Polyvinyl_acetate) (white glue), though it may not be weather resistant. [Shrinky Dinks](https://en.wikipedia.org/wiki/Shrinky_Dinks), made of polystyrene, came in a variety impregnated with luminous zinc sulfide. So protecting a luminous painted surface with a layer of plastic should work.

**Tags:** material-selection, paint


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## 1 answers

### Answer by username_1 on 2021-08-30. Score: 3

I'd try **polyurethane** varnishes.  
They are weatherproof, contrary to standard acrylic varnishes, they are transparent, but may absorb a bit of UV light, as UV is sometimes a catalyst to the reaction to form them ([source : wikipedia](https://en.wikipedia.org/wiki/Polyurethane)) (only a guess here, as I didn't find valuable PU absorption spectrum). It is also stated that polyurethanes with **isocyanates** react with UV light and it discolours them over time, so if you can, try isocyanate-free polyurethane.  
Anyway, it is a very common outer coating protection for wood, so it is not very expensive (found some at 20 €/$ for 250ml).  
You could give it a try and see how it works for you.


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