Adox HC110 Pro Question

In the safety data sheet for Adox HC110 Pro, it contains hydroquinone and a phenidone derivative and it also contains Pyrocatechol.
Does anyone know what the Pyrocatechol does, besides the hydroquinone and Phenidone derivative?

Keith Tapscott. said:

In the safety data sheet for Adox HC110 Pro, it contains hydroquinone and a phenidone derivative and it also contains Pyrocatechol.
Does anyone know what the Pyrocatechol does, besides the hydroquinone and Phenidone derivative?

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Well, it's a developing agent. The original HC-110 also contained pyrocatechol.

Superadditive

Supercalifragiliticexpialidosious

mshchem said:

Supercalifragiliticexpialidosious

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lol

mshchem said:

Superadditive

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Yes, but so is the hydroquinone. I'm wondering if it helps to control contrast or to improve sharpness in some way.

Keith Tapscott. said:

Yes, but so is the hydroquinone. I'm wondering if it helps to control contrast or to improve sharpness in some way.

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Keith Tapscott. said:

Yes, but so is the hydroquinone. I'm wondering if it helps to control contrast or to improve sharpness in some way.

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Looking at the pH of HC-110 (around 9.1 in a typical dilution) pyrocatechol is borderline active on its own. Superadditive effects are not as simple as it seems on the surface. In this case you have a few agents that interact with each other in ways that may be more complex than simply one recharging the other. You may also have different agents active in different regions of the film (e.g. edge of highlights vs highlights vs deep shadow) during development due to localized pH changes and dilution, and the build up of development products.