[alt-photo] Re: Casein source

[Alberto Novo]

Chris, 

> I did a layer of casein on Yupo and on Kwik Print plastic. On both I was able to wipe off pigment like wiping chalk off a chalkboard. However, if what the website says is correct, that if you can wipe paint off you need more binder, then I will go back and revisit Yupo and Kwik Print paper with less pigment/more binder. So until proven guilty, these papers are not out yet.

Which website? 

> Three, the fact that in the ammonia recipe the chemical reaction is created over time with no heat is probably why the ammonium caseinate works so well for me and not the sodium caseinate, that it has the "reactor" in it already which the sodium does not. My sodium caseinate is still a rubbery glob after several days, only usable if heated to a liquid, just as gelatin.

I would cite again US pat. 4,865,953 (1989) where sodium caseinate is used 
with ammonium dichromate to create a photoresist for etching TV screens. The 
composition is:
680 cc of 25% sodium hydroxide
60,000 cc of water
6,000 g of casein
heated at 80°C for 30 minutes.
To this solution is added some wetting agent, and ammonium or sodium 
dichromate in proportion of 5-15% of the casein.
The amount of sodium hydroxide is near 3% of casein, and the solution is 
something less than 10% in casein
The patentees declare that this composition has increased photosensitivity 
and shelf life than similar solutions made with borax. 

> Since Schmincke and Kremer provide a liquid version of casein binder do you think there is a market for the ammonium caseinate powder? Wonder why the paint companies don't provide the ammonium caseinate? There's got to be a reason, perhaps a viscosity reason, that just regular casein is sold only it seems.

Those solutions are for painters and not for alt-printers. I am not a 
painter, but I believe that viscosity might be one among the more important 
properties in painting. 

Alberto
www.grupponamias.com
www.alternativephotography.com/wp/photographers/rodolfo-namias-group