PTEA Question

[Saganich]

I mixed up 100 ml of pTEA yesterday following the usual formula,
100ml TEA
9g ascorbic acid
.22g p (I probably added close to .3)
All from the Formulary.
The Ascorbic and p are about 8 months old but were unopened.
The temp when mixing was about 90C

At first the mixing seemed complete so I stopped mixing then a gooey sticky precipitate formed and it wouldn't mix back. Not much just a bit stuck to the sides and bottom of the beaker.

Is it because I didn't mix long enough? Or perhaps another reason like contamination or bad ingredients?
Thanks,
Chris S.

 

[Tom Hoskinson]

I mixed up 100 ml of pTEA yesterday following the usual formula,
100ml TEA
9g ascorbic acid
.22g p (I probably added close to .3)
All from the Formulary.
The Ascorbic and p are about 8 months old but were unopened.
The temp when mixing was about 90C

At first the mixing seemed complete so I stopped mixing then a gooey sticky precipitate formed and it wouldn't mix back. Not much just a bit stuck to the sides and bottom of the beaker.

Is it because I didn't mix long enough? Or perhaps another reason like contamination or bad ingredients?
Thanks,
Chris S.

Chris, there is probably nothing wrong with your mix. I'll bet your mixture will dissove in water and work fine.

Mixing these homebrews is easiest with a stirring hotplate (Corning, etc.). These magnetic stirring units can often be found used on eBay.

BTW, you can lower the viscosity of the TEA mixture by adding some warm (90-100 F) Propylene Glycol. If you wish, you can dilute TEA 1:1 with Propylene Glycol. The only advantage gained by doing this is viscosity reduction.

 

[Jordan]

Please define "P" so we avoid confusion. Is it phenidone, in which case you're talking about the developer everyone calls "PC-TEA"? Or is it pyro (pyrogallol), in which case you're talking about "P-TEA", a developer Pat Gainer posted about (IIRC) a while ago that contains just pyro and TEA?

 

[Saganich]

Thanks for the response, p stands for phenidone. Didn't know there was a pyro version. I suppose there would be a Metol version as well. Anyway, I was using a hotplate magnetic stiring thing but was unexpectantly rushed for time so I had shut down quicker then anticipated. Just thought I'd through it out there to the experts for an opinion. I suspect it will be OK, I have a test roll to try it out on.
Chris