How many forms of CD3?

Anon Ymous

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Hello

In another thread, @Photo Engineer said that there are as many as 4 forms of CD4:

So, the question is, does CD3 come in different salts as well? The reason I'm asking is because I got a large (~0,5 units) pH difference when mixing an E6 colour developer formula. Of course, there could be several culprits, but considering that I got the right pH for other formulae, the problem might be with my trisodium phosphate, citrazinic acid and CD3.
 

138S

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Anon, I don't know the answer, but let me make a quantitative consideration, CD-3 is 337gr/mol and given the weight of sulfate the salt may carry around 3grs of sulfate more or less per liter for the usual CD-3 dose, if I calculated well.

Let me ask, do you get good results with DIY E-6 chem ? This is something I'd like to try...
 
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GLS

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So, the question is, does CD3 come in different salts as well?

The basicity of the two amines in CD4 and CD3 will be very similar, so yes, I imagine you could easily get different salt forms of CD3. The form obtained will depend on the precise procedure which was used for the synthesis and purification of a particular batch, so may vary from supplier to supplier.
 

Photo Engineer

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The answer is YES. All color developers, being basic, can come as different acid salts depending on manufacturer. So, one must watch out for Molecular Weight. Most agree though not to make HCl salts as they can affect development in various ways. So they are usually H2SO4 salts or p-Toluene Sulfonic Acid salts.

PE
 
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