Pre washing film

Lachlan Young · Nov 11, 2016

LAG said:
Can you (or both of you) tell us what the additive Diethanolamine on T-max Developer do?

The Diethanolamine-Sulfur Dioxide complex in HC-110 and TMAX developer is, as I understand it, intended as a non aqueous alkali in place of aqueous solutions of sulfites, carbonates, hydroxides etc, enabling a highly concentrated developer with an exceptional shelf life to be made. Again, from what I understand, the complex has a multifunctional role as an alkali, preservative & grain solvent - though Ron (Photo Engineer) will know far more about this.

LAG said:
I have some other questions like: don’t you know any developer with a wetting agent on it?, in your years of experience, have you never used (or noticed) a wetting agent on your developer? or have you never used a wetting agent on your (water) pre-wash bath? … but as I have already mentioned above, there’re some other outstanding issues without any answer (and without hope for my part) on post #81 and now on #118 and #120, and this very one.

Essentially every developer in use today will feel 'soapy' - they're alkaline!

LAG · Nov 11, 2016

Lachlan Young said:
The Diethanolamine-Sulfur Dioxide complex ...

Excuse me Lachan Young

I asked for (a) Diethanolamine, not for (b) Diethanolamine-Sulfur Dioxide Complex, both are present but with different concentrate (%)

Let's wait then!

Lachlan Young · Nov 11, 2016

LAG said:
Excuse me Lachan Young

I asked for (a) Diethanolamine, not for (b) Diethanolamine-Sulfur Dioxide Complex, both are present but with different concentrate (%)

Let's wait then!

It's probably added for pH adjustment.

LAG · Nov 11, 2016

Lachlan Young said:
It's probably added for pH adjustment.

The pH is a mission for a Alkali agents. That's not the reason, to push the pH you use Alkali as well not Diethanolamine

Photo Engineer · Nov 11, 2016

LAG, Diethanol amine serves two purposes. One is to act as a source of alkali and the other is to act as a silver halide solvent. It is often balanced by the use of Tri Ethanol amine in a weak analogy to Carbonate - Bicarbonate buffer mixtures.

Now, that is the response of one who has on the market, one developer, one fixer and one blix formula.

Please name a real surfactant or humectant in a developer. HINT - a humectant must remain in the emulsion to be a humectant, and it cannot be in a liquid developer because water is already present.

PE

LAG · Nov 11, 2016

Excuse me Photo Engineer

Diethanolamine, DiEthan(O)l Amine (DEA or DE(O)A is an inhibitor, also a wetting agent, and is the name your are looking for. Again one answer from me ... I am glad to help. I thought you knew it!

But why does everybody ask questions and do not answer anyone? What are you guys hiding or playing? or is it only sturbornness?

Photo Engineer, perhaps are you trying to tell us that you don't know any developer with wetting agent??? or trying to divert the focus playing around with this additive?

Please stick to the point, I love merry-go-rounds, but only if they have a way to stop

Best

Hexavalent · Nov 11, 2016

LAG said:
The pH is a mission for a Alkali agents. That's not the reason, to push the pH you use Alkali as well not Diethanolamine

An 'alkali' is not required to "push the pH", a base works as well. "Alkali" is a loose term, often used incorrectly.

Photo Engineer · Nov 11, 2016

LAG said:
Excuse me Photo Engineer

Diethanolamine, DiEthan(O)l Amine (DEA or DE(O)A is an inhibitor, also a wetting agent, and is the name your are looking for. Again one answer from me ... I am glad to help. I thought you knew it!

But why does everybody ask questions and do not answer anyone? What are you guys hiding or playing? or is it only sturbornness?

Photo Engineer, perhaps are you trying to tell us that you don't know any developer with wetting agent??? or trying to divert the focus playing around with this additive?

Please stick to the point, I love merry-go-rounds, but only if they have a way to stop

Best

Wetting agents fall in to 3 classes, namely: Non-ionic, Anionic and Cationic. They are neutral in pH as sold. Photo flo is a nonionic surfactant while dish soaps are often cationic such as Di-Nonyl Napthalene Sulfonic Acid (DNNSA). Diethanol amine is properly a basic compound. Due to its nature it is also a weak Silver Halide solvent and as such is used in many developers. Triethanol amine is often contaminated by Diethanol amine and this causes pH to vary and Silver Halide properties to vary. The Diethanol Amine - SO2 complex or adduct is present as a carrier for Sulfite ion which acts as a preservative for the HQ, Phenidone or Metol which may be present. This is an answer not a question.

Surfactants are generally used very dilute such as Photo Flo 200 which is 1 ml or less / 200 ml of solution. They cause severe foam if mishandled, and change surface and viscosity properties. Although Diethanol amine can have surfactant properties, as noted by some, that is not its most notable property, at least in photography.

Common photographic surfactants are Saponin, Triton X 100 and Triton X 200 along with the DNNSA noted above.

Humectants are chemicals that force absorption of water, or retain water in a carrier such as paper or film. As such, they are washed out if used in developers and should be used for effect only in final rinse or stabilizer baths. They have no use in any solution, but rather are activated or become active only when the carrier is dried. Useful humectants include sorbitol and glycerol. They prevent cracking in dry photo materials and help preserve the final image depending on how they are used.

There, is that enough for you?

PE

Hexavalent · Nov 11, 2016

LAG said:
This thread is getting funnier, isn´t it? I like this sense of humor. Thank you

Excuse me Hexavalent,

so your “such us” question hid a trap behind, oh, naughty boy! Can I play this game too?

I asked a question in response to your statement "Many developers already include in their formulation pre-wetting agents".
It is a fair question. Your response however, did not support your assertion, in fact it, the examples (Ilford ID11, Kodak T-Max Dev) you gave contradict your position. TEA may have a weak "wetting" action, but it is not it's primary function in a developer.

LAG · Nov 11, 2016

Hexavalent said:
I asked a question in response to your statement "Many developers already include in their formulation pre-wetting agents".

It is a fair question. Your response however, did not support your assertion, in fact it, the examples (Ilford ID11, Kodak T-Max Dev) you gave contradict your position. .

Really? ...

Hexavalent said:
… TEA may have a weak "wetting" action, but it is not it's primary function in a developer.

I like your sense of humour

Hexavalent · Nov 11, 2016

LAG said:
Really? ...

Yes Really.

LAG · Nov 11, 2016

Hexavalent said:
Yes Really.

No offense but then you have not understood a word! (in my opinion, of course) I am not saying that you are going to need it, but just in case: Best of luck!

Photo Engineer said:
There, is that enough for you?

Excuse me Photo Engineer

Enough?

Photo Engineer said:
... Although Diethanol amine can have surfactant properties ...

Only with this it would have been enough, and it was about time to write it down and admit it, too! Thank you very much to tell me I was right and for your efforts anyway, naturally!

Regards

p.s. It seems this thread needs a final wash with a wetting agent to break the tension, now we all know where to find more than one, allow to dry after cleaning.

Hexavalent · Nov 11, 2016

LAG said:
No offense but then you have not understood a word! (in my opinion, of course) I am not saying that you are going to need it, but just in case: Best of luck!

Thanks, but I don't need any of your luck. It is indeed difficult to understand what you've written, as it is patently false and/or based upon a very rudimentary knowledge of photo-chemistry.

Yawn.

Photo Engineer · Nov 11, 2016

I assert again that Diethanol Amine is not used as a surfactant in the photo industry, but it has many other uses there as noted above. In fact, although DEA has some surfactant properties, I would have to ask in what system. Is it oil based, water based, alcohol based? What? AAMOF, Salt, common Salt is a surfactant in the sense that it changes the surface tension and rheology of any water based system containing it. That is the purpose of any surfactant. And, while DEA may have mild surfactant properties in some solvent system, it varies with pH as do Anionic and Cationic surfactants. That is why it would be difficult to control or use DEA for this purpose. In fact, one must be very careful in TEA developers such that DEA is held to a minimum so that solvent and pH effects are avoided.

PE

Craig · Nov 12, 2016

I kind of resurrected this thread with my question of why would Pyrocat developer recommend a pre wet, yet Ilford does not; we don't seem to have uncovered any particular technical reason why there would be the discrepancy in the recommendations, so perhaps we could put this thread back to sleep until a technical reason (i.e. not opinion or anecdotal experience) appears?

RauschenOderKorn · Nov 12, 2016

RalphLambrecht said:
Jobs recommends dropping the pre wash

Can you provide a source for that please?

Photo Engineer · Nov 12, 2016

It is a matter of uniformity from my direct tests. The simple experiment I proposed earlier might show you how it works.

PE

Craig · Nov 12, 2016

Photo Engineer said:
It is a matter of uniformity from my direct tests. The simple experiment I proposed earlier might show you how it works.
PE

I don't doubt you for a moment PE, I'm more curious why Ilford says on the HP5 Plus fact sheet: "A pre-rinse is not recommended as it can lead to uneven processing".

Absent evidence to the contrary, I will always assume the manufacturer knows what they are talking about and wouldn't have put such a statement on the fact sheet if a pre rinse was at worst of no effect. If there was a benefit or it did nothing, surely they wouldn't say "not recommended"?

Photo Engineer · Nov 12, 2016

Craig, I have no idea why Ilford does anything. Sorry.

We did not use prewet in dip and dunk or in Nitrogen burst systems, but otherwise I have used a prewet. The reason for the prewet is the slow and uneven wetting rate in rotary processes or with short development times.

PE

Gerald C Koch · Nov 12, 2016

Lachlan Young said:
The Diethanolamine-Sulfur Dioxide complex in HC-110 and TMAX developer is, as I understand it, intended as a non aqueous alkali in place of aqueous solutions of sulfites, carbonates, hydroxides etc, enabling a highly concentrated developer with an exceptional shelf life to be made. Again, from what I understand, the complex has a multifunctional role as an alkali, preservative & grain solvent - though Ron (Photo Engineer) will know far more about this.

Essentially every developer in use today will feel 'soapy' - they're alkaline!

No The sulfur dioxide adduct takes the place of sodium sulfite. When the HC-110 is mixed with water the adduct supplies sulfite ions such as are present in other developers. The alkalinity comes from another source. In HC-110 the pH is controlled by the ethanolamine and diethanolamine.

Lachlan Young · Nov 13, 2016

Gerald C Koch said:
No The sulfur dioxide adduct takes the place of sodium sulfite. When the HC-110 is mixed with water the adduct supplies sulfite ions such as are present in other developers. The alkalinity comes from another source. In HC-110 the pH is controlled by the ethanolamine and diethanolamine.

So why does the (late 2000s) MSDS for TMAX developer not have any other significant quantity of a basic component than the SO2 adduct? Anything alkaline is almost always in the MSDS.

I should add that the most up-to-date MSDS omits all mention of an adduct & simply states Diethanolamine & Sulphur Dioxide for both TMAX & HC-110.

Photo Engineer · Nov 13, 2016

To "build" a stable adduct, excess amine is needed to prevent SO2 "leaking". Those are simplified, but express things. This excess amine is the base. It is a mix of DEA and TEA and is quite stable. It also allows the omission of water from the liquid concentrate.

PE

Lachlan Young · Nov 13, 2016

Photo Engineer said:
To "build" a stable adduct, excess amine is needed to prevent SO2 "leaking". Those are simplified, but express things. This excess amine is the base. It is a mix of DEA and TEA and is quite stable. It also allows the omission of water from the liquid concentrate.

PE

Cheers for the information!

Pre washing film

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