did kodachrome film chemicals consist ofHydrochloric Acid, Sulphuric Acid, Benzene, and Potassium Permanganate

[derek_morrison]

<p>Hi everyone, I am researching an x-ray dye that was developed by Eastman Kodak using the following chemicals.... Hydrochloric Acid, Sulphuric Acid, Benzene and Potassium Permanganate. There is no denying that Kodak developed this x-ray dye using waste-water of film processing, what I am trying to figure out is what film, as it initially happened in 1936 its my belief its kodachrome. However, I DONT NOT know if these chemicals were used in its processing.<br>

I am hoping we have someone on here that can help me with this, as my research has come to a stop, not good.<br>

Thanks<br>

Derek [in Australia]<br>

<a href="mailto:ctensw@gmail.com">ctensw@gmail.com</a> </p>

[larrydressler]

<p>Well that formula does sound like a reversal bleach solution in part but in 1936 Kodak was also working on Kodacolor negative film but I believe it was a 2 filter not 3 type film. 1935 Kodachrome was introduced. </p>

[Aoresteen]

<p>Go over to APUG.ORG and contact user Photo Engineer.</p>

[larrydressler]

<p>Or ask Ron Andrews here. He worked for Kodak and with Kodachrome.</p>

[randrew1]

<p>"There is no denying that Kodak developed this x-ray dye using waste-water of film processing"<br>

Why would they derive a dye from waste-water? Kodak generally sought to tightly control starting materials. They might have used the same chemicals used elsewhere, but I doubt they used waste-water.<br>

I don't have the original Kodachrome formulas. I doubt that Potassium Permanganate was used anywhere in the process. As Larry says, it was used as a B&W reversal bleach. </p>

[Alan Marcus]

<p>With few exceptions, the developing agents we use are related to benzene. Initially derived from coal, it is now synthesized. Benzene is the basic building block of organic chemistry. Most photographic developers are benzene with side chains. In the 1930’s and earlier, black & white reversal processes were in vogue. These yielded black & white motion picture films and black & white slides (nicknamed “lantern slides”). Reversal motion picture film processing was available in most major municipalities, all over the world. <br>

The bleach step formula – a common one was Kodak R-21A however, Agfa, Ilford, GAF, Gevert, DuPont, and countless others published formulas that only varied slightly as to amounts.<br>

Distilled Water 700ml<br>

Potassium Dichromate 50g<br>

Concentrated Sulfuric Acid 50ml<br>

Add water to make 1000ml<br>

<br>

Now all photographic processing houses of that era used copious amounts of water to rinse and then bathe the film in a final wash. There was no attempt until late in the 20^th century to treat wash water to extract residual chemicals. We are talking about silver. <br>

<br>

Dye in photo film has been around since Hermann Wihelm Vogel, Professor Photo Science Berlin Technical, added aniline dyes to photographic emulsion in 1873. Heretofore film was only sensitive to short wavelengths like X-ray, UV, violet and blue. Vogel’s dye additions paved the way to extend film sensitivity into the green and red regions of the spectrum.<br>

<br>

I also believe that it would be impractical thus highly unlikely that anyone would pre-treat wastewater from a photo lab in order to extract constituents to be used to make dye. On the other hand, in the Kodachrome process, the color developers contained used but good ingredients. Because of their cost, it was economical to precipitate them out and then re-use. Additionally, in most super big photo processing labs, used chemicals were restored by various means and reused. </p>