[somorastik]

Hello,

I ran into a problem while experimenting with optical fibers. I use the standard Corning SMF28 fiber, which has a silica glass core and UV-cured acrylic coating, which I need to dissolve.
I tried dichlor methan CH2Cl2, Chloroform CHCl3 both with the same result, the coating got sepparated from the fiber, but not dissolved.
I tried the Piranha solution as well, at 90°C a mixture of sulfuric acid and hydrogen peroxide, with no good result.
Acetone did nothing.

I am not quite sure about the type of material used for the coating, the only thing I know is that it is UV-cured acrylic, as I mentioned.

Any ideas please?

Thank you

Raz

[Hunter2]

Try Toluene or Dimethylformamide

[curiouscat]

Hot Piranha not dissolving it is impressive in my book.

[curiouscat]

Out of curiosity, why do you want to get rid of the coating?

[Enthalpy]

If you access an oxygen plasma - the kind of lovely stuff used in semiconductor processing - it should nicely delete organics but leave silica untouched. Try to protect the fiber (alumina plate) where the Pmma shall stay.

Would a torch do the job?  With much oxygen, little acetylene, and staying far enough from the fibre...? Pollution of silica is the limit.

Ozone?

Singlet oxygen? (OK, less easy)

[somorastik]

Thank you so much for the answers!

First of all, oxygen plazma did not help either.
The reason why I want to dissolve the coating is to clean a Phase mask, somwhat simmilar to the ones used in creating semiconductors.

Some of the coating got evaporated on to the phase mask during the laser etching process. The phase mask is very fragile thing, so no mechanical cleaning what so ever.
I rulled out using a torch to clean it, might cause more dammage.

The problem is, I am not sure what the coating is really made of since, the manufacturer, only states, it is made of UV-cured Acrylic.

Any other suggestions? I am willing to try anything that I can, since this is key to my research.

It might not be the case, but could the UV-cured Acrylic, change somewhat during the evaporation?

Thank you so much!

[curiouscat]

How long did you expose to Piranha / H2SO4 + h2O2

[somorastik]

I exposed it about 45-50 minutes at around 90°C. The sollution was freshly prepaired.