Paint pigments

[kiddhill20]

Hello all,

I heard from someone that there are paint pigments that are currently encapsulated in silicon (for what reason I'm not sure) but I haven't been able to find any information concerning this.

Can anyone suggest a good place to start? Thanks very much.

 

[Compositepro]

Perhaps he meant silicone or was refering to silane surface treatments. Silicon make no sense in this context.

 

[kiddhill20]

Thanks for the reply, Compositepro. I found it's silica. Pigment manufacturers use a slurry of the pigment together with a sodium silicate solution at a particular pH to coat the pigments. (Process has actually been around since the 1970s... just looked in the wrong places...)

I have read that it is the hydrophilicity of the pigment surface that enables silica to deposit and form a coating. Does anyone know of another reason that I may not be aware of?

 

[Compositepro]

Sodium silicate is also know as water glass. I believe its main function is as a high temperature binder. So those pigments are probably used for high temperature paints.