Concentrated long lasting paper developer formula

[ruilourosa]

here it´s mono...

10gr Kbr + benzotriazole? or just kbr?

i will add some benzotriazole and try to find a good place for neutral tones avoiding fog

i think i managed to get 150gr of Sod. Carbonate into solution, but i really think that potassium hidroxide helped a bit, maybe just for heating the solution again



Thanks!!!!!!

Rui Lourosa

 

[Ian Grant]

Well you should have added 173.4g Sodium Carbonate monohydrate, but as you added Potassium Hydroxide that'll make up for the difference. 5g Bromide with Benzotriazole, or 10g without.

Ian

 

[ruilourosa]

Thanks for the guidelines!!

 

[koraks]

actually the anhydrous is the commonest form in Europe.

Not my part of europe, that's for sure. We get decahydrate and monohydrate, mostly. Anhydrous is also not a very good choice since it's gyroscopic and will a sorb moisture to become monohydrate, so with an opened container of anhydrous, you're never quite sure what the ratio between the two of them is.
If there's a choice I'd always recommend getting monohydrate; it's stable and most formulas are based on it (no conversion necessary).

 

[Ian Grant]

Sodium Carbonate anhydrous is only very mildly hygroscopic, it takes years to deteriorate in a sealed container. Sugar is hygroscopic, as are a number of photographic chemicals like Potassium Bromide. It's not an issue.

Ian

 

[koraks]

it takes tears to deteriorate

Can't help but smile at this typo

 

[Ian Grant]

You mean like

Anhydrous is also not a very good choice since it's gyroscopic and will a sorb moisture.

The thought of molecules gyrating

Yes, tears would change the state of anhydrous carbonate.

Ian

 

[koraks]

Autocorrect mayhem!
Will anhydrous carbonate sob moisture...