Rodinal version with best shelf life

[Nitroplait]

Unopened.
Unknown age (but pre Gevaert fusion).
Brown glass bottle with a beautiful bakelite cap. The cap was shrink wrapped in some “cellophane” like material which crumbled to dust when I touched it.
The content is completely crystallized.

 

[pentaxuser]

I wonder if I should move my Adox Rodinal to a glass bottle. So far I've kept it in its original plastic bottle.

All I can say is that I bought the original Agfa Rodinal in 2005. It had been reduced in price a little as the shop was trying to clear out older stock. It was and still is in its original white plastic bottle. I used it a couple of months ago and it worked fine

pentaxuser

 

[dcy]

All I can say is that I bought the original Agfa Rodinal in 2005. It had been reduced in price a little as the shop was trying to clear out older stock. It was and still is in its original white plastic bottle. I used it a couple of months ago and it worked fine

pentaxuser

Thanks. That's an impressive shelf life. I'll leave my Adox one in the original bottle then.

 

[relistan]

I have a half used plastic bottle of ADOX Adonal (Rodinal) bought in 2009. It still works great when I occasionally use it.

 

[P C Headland]

All I can say is that I bought the original Agfa Rodinal in 2005. It had been reduced in price a little as the shop was trying to clear out older stock. It was and still is in its original white plastic bottle. I used it a couple of months ago and it worked fine

pentaxuser

Similarly with me. I’ve got a couple of bottles bought in the early noughties. The 500ml one I’m currently using was opened in the late noughties, is now very dark and still works perfectly ok.

 

[YoIaMoNwater]

I also want to add that Fomadon R09 has a pH of 11.8 whereas Adox Rodinal/Adonal has a pH of >13. I bet the higher pH/higher hydroxide content in Adox's version allows it to keep better.

 

[koraks]

I also want to add that Fomadon R09 has a pH of 11.8 whereas Adox Rodinal/Adonal has a pH of >13. I bet the higher pH/higher hydroxide content in Adox's version allows it to keep better.

I really doubt that; I'd expect the opposite. Higher pH means in principle there's more opportunity for the developing agent to oxidize and be rendered inactive. In rodinal, a copious amount of sulfite is present to provent this from happening.
The hydroxide content will need to be set such that the target pH of the working strength developer is met; this by necessity will have to be the same pH for the foma and the adox product; both are supposed to Rodinal variants/clones, after all, so logically the working strength solution will need to be equivalent. Both are based on potassium hydroxide so we can quite safely assume that the amount of hydroxide in both these products will be roughly the same.

The difference in pH is likely due to the effect of adjuvants (note e.g. the zinc powder) in the bottled mix; I personally wouldn't pay much attention to the pH of a rodinal concentrate since it can be qualified in any case as "godawful high". In the end, it doesn't really matter whether it's nearly 12 or over 13; either way it's as alkaline as things can realistically get.

 

[YoIaMoNwater]

I really doubt that; I'd expect the opposite. Higher pH means in principle there's more opportunity for the developing agent to oxidize and be rendered inactive. In rodinal, a copious amount of sulfite is present to provent this from happening.
The hydroxide content will need to be set such that the target pH of the working strength developer is met; this by necessity will have to be the same pH for the foma and the adox product; both are supposed to Rodinal variants/clones, after all, so logically the working strength solution will need to be equivalent. Both are based on potassium hydroxide so we can quite safely assume that the amount of hydroxide in both these products will be roughly the same.

The difference in pH is likely due to the effect of adjuvants (note e.g. the zinc powder) in the bottled mix; I personally wouldn't pay much attention to the pH of a rodinal concentrate since it can be qualified in any case as "godawful high". In the end, it doesn't really matter whether it's nearly 12 or over 13; either way it's as alkaline as things can realistically get.

pH of zinc will not get to that high. pH of hydroxide will, since well, it's literally OH- that raises the pH level. We are not talking about working strength solution pH but stock solution pH. So if everything else in Rodinal is exactly the same for both Foma and Adox products, then the only reasonable ingredient that can raise it's pH from 11.8 to 13 has to be more hydroxide.

 

[koraks]

the only reasonable ingredient that can raise it's pH from 11.8 to 13 has to be more hydroxide.

Just do the math using different concentrations of NaOH with these pH numbers. You'll realize that there has to be more going on and that a difference in NaOH concentration cannot be the full story. Keep also the w/v percentage of NaOH listed in the SDS in mind.

 

[BMbikerider]

As Matt said in post 3 the brown bottles come to the rescue again. I have used them for many years for C41, RA4 and also Rodinal. 100cc bottles with the conical polythene insert in the cap are 100% airtight and a 1/2 litre bottle of Adox version will decant nicely into 5 of these. These are as we say in UK as cheap as chips and I have dozens of them. All washable and reusable as many times as you wish. (just don't forget to lable the bottles with what they contain as I found out it can be a mistake not to!)

 

[Samu]

I've used the R09 Rodinal and had the same experience--about 18 months then nothing.

Which one? There are many Rodinal clones in the market called R09.

 

[abruzzi]

Which one? There are many Rodinal clones in the market called R09.

Searching images, it look like it was Compard--before Compard was cross branded "Rollei". The bottle wasn't really branded:

 

[MattKing]

R09 was a historic version/type of Rodinal with an important position in the evolutionary timeframe of Rodinal.
The "recipe" for R09 appears to either be in the public domain, or easily licensed.
So it wouldn't be surprising to see R09 on different bottles of developer, from different suppliers.
Some suppliers prefer to use their own brand name. For example, Blazinal in CanaDda.
Other suppliers prefer to identify their R09 with its heritage.