Saturday, April 17, 2021

A Whiter White Paint

Scientists at Purdue University have developed a white pigment that they say is significantly whiter than existing pigments. A surface looks white because it reflects back a diffuse version of most of the the light hitting it. 

This new pigment reflects back up to 98% of the sunlight, while commercially available white pigments only reflect back between 80 and 90 percent.


 
Professor Xiulin Ruan with a sample of his "ultra-white" paint, courtesy BBC and Purdue

According to the BBC:

"The new paint contains a compound called barium sulfate, which is also used to make photo paper and cosmetics. 'We used a very high concentration of the compound particles,' explained Prof Ruan. 'And we use lots of different sizes of particles, because sunlight has different colours at the different wavelength.' How much each particle scatters light depends on its size, 'so we deliberately used different particle sizes to scatter each wavelength.'"

The new white pigment should be more reasonably affordable and available compared to the ultra black "Vantablack" or the new blue pigment that I mentioned in 2016.

It looks intriguing. I'd like to see how it looks next to Titanium or lead white. But I don't know how useful it would be to me as a painter because I almost always want to darken my lightest light and raise my darkest dark in a picture anyway. The challenge isn't pushing the absolute range of values but rather organizing the tones so that the picture makes sense.
--
Thanks, Joseph and Dan


5 comments:

forrie said...

You can get barium sulphate powder on Amazon; high quality. I need to find out the ground (grade), but I wonder about mixing some of this in white paint -- for applications that rely on the reflectivity of the white background.

forrie said...

I'm a fan, Forrest.

Marina said...

I don’t think this paint will benefit artists, it’s meant more for commercial use. I read that it will reduce the need for air conditioning in offices, for example.

forrie said...

They put chalk in gesso, why not add barium sulphate to some white paint? If it reflects more light, and it suits your needs, go for it.

Skadjer said...

Use it just for the highlights of the eyes. :D