I MADE A DEVELOPER TODAY, YES A NEW ONE!

[ruilourosa]

hello


today i think i got closer than ever, i think close enough, to get a highly dilutable neutral tone normal contrast paper developer, i started with some msds sheets and got with this:

h2o 52ºc 750ml
phenidone 1gm
Sodium sulfite 100gm
Hidroquinone 100gm
Sodium Carbonate 150gm
potassium bromide 5 gm
Triethanolamine 100ml
h2o to 1 liter

dilute 1+9



it develops fast and gives good blacks as well as no fog in slightly old paper for 2-3 minutes development, the scale is identical to d-72


next:


i think i am pouring too much hidroquinone, maybe half would be enough, also i think a direct substitution by sodium ascorbate is possible,

i use the triethanolamine because it´s hard to dissolve more than 150-200 gm of sodium carbonate is 50ºwater


i could increase 50 gm to the sodium sulfite amount, but i do not see much benefits, but is 10gm per liter of working solution enough to activate the PQ superadditivitty???????????


well another aproach would be a x10 d72 or maybe E72 but i find really on the limit to dilute 270 gr of sodium cabonate in one liter of water, i also do not know the life espectancy of this kind of concentrate

triethanolamine also improves tray life (i was told)


can anyone say a thing or two


please do not ask why i don´t use d-72 or dektol or multigrade or so! i´m just trying to formulate a developer that is cheap and convenient



Thanks

Rui Lourosa

 

[Christopher Walrath]

More knowledgable will coment for sure. But I see a glaring thing with your recipe. Your amounts for sodium sulfite, sodium carbonate and and potassium bromide are double that of the D-72 recipe and the hydroquinone is 800% over the amount in D-72. I know this is an initial recipe. How did you arrive at your amounts of these ingredients to be added into the mix?

Don't take me as an authority on chemistry. I admittedly have a databook that I am referring to. Just some differences I note. Hoping to make you think as well as to gain some insight for myself along the way.

 

[ruilourosa]

well i based myself in some formulas like the ilford universal concentrated liquid paper developer (a formula that i do not enjoy as it is because of high fog and short tray life, the first easely correctable by adding more bromide) and some early findings in some msds sheets, but yes hidroquinone is way far of that 40:1 to phenidone that gainer tested, well i will try to correct that in the future. but i did not have any problem, like fog or gray blacks or high or low contrast, but i think that it´s too much hidroquinone there doing nothing, in the future i will use half or just 40gms (to 1gm of phenidone) or even switch to sodium ascorbate.


i´m having doubts in the alkali department d-72 uses around 27gm per liter of working solution but it´s too much to put in the concentrate, so i substituted it by TEA but a bit on the empirical side, i substituted 100ml of Tea by 100gm of sodium carbonate, or more or less that.

i will reduce the hidroquinone amount or substitute it by sodium ascorbate, i will post results, i gess it will get similar to Tektol but cheap as a pechincha!

Rui Lourosa

 

[ruilourosa]

done! i cut half of the hidroquinone, it works perfectly in the same way, i´ll check the life span

i already ordered some ascorbate i´ll post my tests


Rui Lourosa

 

[Steve Smith]

I'm no chemist either but I vaguely know about a developer being an acid buffered to an alkaline with the addition of something to prevent early oxidisation.

Do the increased levels of ingredients detailed by Christopher lead to early oxidisation or is one of those an anti-oxidant itself?


Steve.

 

[Ian Grant]

Looks like you're re-inventing Ilford's ID-62 developer which is the basis of most of Ilford's commercial paper developers. This is a concentrated version, however I replace the Sodium Carbonate with Potassium carbonate & Sodium or Potassium Hydroxide as it keeps longer without any crystallisation of the carbonate etc. (This is normal for commercial liquid developers like PQ Universal, Mutigrade, Neutol, Liquid Dextol/Polymax etc).

Ilford ID-62 PQ Developer (Concentrated Stock Solution) - Cool Tones

Phenidone 1.25 g
Sodium Sulphite (anh) 125 g
Hydroquinone 30 g
Sodium Carbonate (anh) 150 g
Potassium Bromide 5 g
Benzotriazole 1% soln 50 ml
Water to 1 litre

Use 1 + 9

Ian