[Leica] Xtol dev times - PC-TEA

[craig at craigschroeder.com (Craig Schroeder)]

I've had good luck using propylene glycol in place of some of the TEA 
and reducing some viscosity issues.  My basement darkroom in my northern 
climate left me with solid PC-TEA in winter when I first started 
experimenting with it.  Part of why I wanted to use a long-shelf life 
concentrate was for fitting in with my sporadic trips into the darkroom 
and knowing I had trustworthy chemical ready to go.  With the fussing 
around to get my PC-TEA re-liquefied, it was losing part of its appeal 
for my application.  Another plus of the PG is that ascorbic acid and 
phenidone go into suspension much easier with less heating and then I 
can top up with the TEA.  The TEA based concoctions I've experimented 
with seem to end up with very different freeze points and PC-TEA is the 
only one that I've had problems with at the temperatures that my 
darkroom tends to settle to in the winter.

Mike Durling wrote:

> Maybe I better reiterate that it is the stock solution that has no 
> water.  You dilute the stock with water at a 1:50 ratio.  A little 
> goes a long way.  The Triethanolamine forms an alkaline when mixed 
> with water.  The secret of its longlevity is that nothing reacts with 
> it until you add the water.  Photographically this means that you 
> don't need sulfite, which as you know, eats away at the grain and 
> sharpness.
>
> Now the viscosity is another thing altogether.  When I got mine it was 
> solid, like a rock.  I had to leave it in hot water for quite some 
> time to get it to melt.  Once it was melted it seemed to say that way 
> in a moderately warm house.  The stock solution is also a liquid.  
> Looks kinda like a thick rodinal or maybe maple syrup.
>
> Mike D
>