Hydrophilic Coating

[will123123]

I am trying to find a commercially available hydrophilic coating, such that when a drop of water is placed on the DRY surface treated with this coating that it immediately spreads out to form a very thin layer. Other less important requirements is some resistance against mild abrasion and organic solvents.


Can anyone advise? Thank you.

 

[IRstuff]

I don't think that's possible with water without mechanical help. There are two fundamental problems:
> surface tension of water is quite high, which would want to keep the water from spreading
> as the fluid spreads, there is less mass gradient at the leading edge, which slows down the process

What I have seen that works with solvent-based fluids is a spinning stage that uses the centrifugal effect to drag the fluid across a surface. Uniformity on the order of a few percent are possible. Looks for semiconductor photoresist application machinery.

Alternately, you might be able dunk the surface and withdraw it at a fixed rate.

TTFN
faq731-376

 

[Compositepro]

Hydrophyllic polymers and ceramic coatings will work. A rusty steel surface spreads water well as long as its clean of oil. Porosity in the coating will help through capillary action.