Rodinal

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Rodinal is the name of a popular concentrated liquid black-and-white film and paper developer, introduced by Agfa in 1892 and is a solution of sulphite and water, containing an alkali salt of para-aminophenol and no excess of caustic alkali (hydroxide). The original formula was patented in 1891.

Ilford introduced its equivalent p-aminophenol developer Certinal in 1907/8. C.E.K. Mees of Wratten & Wainwright (UK) investigated p-aminophenol as a developing agent around the same time. He went on to become head of research at Kodak. Kodak released Kodinol, their Rodinal clone, in Europe a few years later (before WWII, it was never made or sold in the US).

When Germany was split up to form the GDR and FRG so did Rodinal. Orwo for the GDR east side and Agfa for FRG west side, with each side evolving their own formulation.

Calbe (the former chemical division of Orwo) and some of the former distributors of Rodinal use the name R-09 (Rodinal formula number 9, circa 1945 revision). This older formulation in various names (at the time can also be called Rodinal in many regions) has appeared along side the Agfa version for decades in many regions. Foma sold it as Fomadon R09 for bottles made before 2008. Adox sold it as Adolux APH09.

When Agfa merged with Gevaert in 1964 they reformulated Rodinal, cutting the p-aminophenol from 50g per litre to 40g per litre, and increasing the pH by adding an excess of potassium hydroxide. Orwo retained the previous formulation.

After Agfa's exit of photo chemical distribution, the lab that produced it became an independent a&o Imaging Solutions. They started rebranding it as A&O Agfa Rodinal for a brief time, but due to legal issues (2006-2014) the trade name Rodinal can no longer be used, even though it was still being made in the same former Agfa factory. After which the Agfa chemicals were no longer being sold for small individual use, but rather for bulk 200 liter drums. Others began repackaging and created own names, like Adox calling it Adonal and confusingly the one packaged from Compared AG called it R09 One Shot. In Canada, it was available as Blazinal. Foma calls it Fomadon R09 for bottles made after 2008. Connect Chemicals, took over, so after many changes of ownership, the lab that produced Rodinal for Agfa no longer produces Agfa chemicals.

As of 2013 or so, many of the distributed developers that used the (1960's) formulation changed to the older R-09 or another newly created revision from Tetenal. Compard AG in 2013 started using a formulation from Tetenal for R09 One Shot. Adox hired many of the technicians responsible for Agfa chemicals and recreated the formulation thereby bottling it in their own factory. Starting in 2014, Adox reacquired the trade name and are allowed to use the Rodinal name in the United States. Adonal is still used in other regions.



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