Potassium Dichromate vs. Sodium Dichromate: Direct Positive Photobooth Process

[Ian Grant]

In reality there are probably quite a few papers you could use, the difficulty is finding a company who would slit it to the right width for you.

EFKE or Foma might be a better bet than Russia or China. Foma have just built a new slitting plant, they slit colour paper for Fuji

Ian

[lizzybordan]

Hi there,

I am really surprised you are having trouble getting product as I manufacture such items for other people!!! Where are you and would you like some info and pricing on our products?

But, I was wondering the same thing here. I am making some for a customer when I found out the potassium dichromate is very hard to get here on the west coast. I have some sodium dichromate and wondered if it could be used in our formula. So did it work for you? Any problems? Please let us know.

Thanks
Liz

[dr5chrome]

In this case use Sodium Dichromate. It will work better for this process. Potassium is best for film.

dw

[lizzybordan]

Thank you!!! So you think the sodium dichromate will work better? Maybe I should make a gallon and have my customer try it first. She has been using this for so long now it is hard to get them to try something new when the old is working just fine....but it would be easier for me!!!

Thanks again.
Liz

[Photo Engineer]

At equal molar concentrations, there is no reason why Sodium or Potassium Dichromate should differ substantially in action on films. Sodium salts are often more prevalent in the US and Potassium salts are more prevalent in Europe just due to abundance of the ingredients.

Potassium Dichromate is certainly more readily available on the open market from what I can tell.

PE