AmDi

Dichromated Gelatin.
Tony DCG
Posts: 147
Joined: Thu Jan 08, 2015 1:47 pm

AmDi

Post by Tony DCG »

I am pretty careful when it comes to dealing with AmDi. I know there is risk involved with Cr6 and have a pretty strict regement in dealing with it.
I run a hepa filter pretty often in the lab. I wipe down surfaces with MS and try to keep that stuff inside my lab.

My excess AmDi is placed in a milk carton in which sits on a top shelf. I notice that when I leave it out in goes from orange to brown. I am guessing it is converting from Cr6 to Cr3 which is a bit less harmful.

My question is if a small piece of AmDi did get loose and is on a surface, and that surface is exposed to light will it convert to Cr3 or does it need something to cross link with?

I was almost thinking of adding a flood light as part of the cleaning process :? Not just for that but also unexposed coated plates that need to be reprocessed and those exposed plates that have thicker film and has a touch of orange.
MilanKarakas

AmDi

Post by MilanKarakas »

Tony DCG wrote:I am pretty careful when it comes to dealing with AmDi. I know there is risk involved with Cr6 and have a pretty strict regement in dealing with it.
I run a hepa filter pretty often in the lab. I wipe down surfaces with MS and try to keep that stuff inside my lab.

My excess AmDi is placed in a milk carton in which sits on a top shelf. I notice that when I leave it out in goes from orange to brown. I am guessing it is converting from Cr6 to Cr3 which is a bit less harmful.

My question is if a small piece of AmDi did get loose and is on a surface, and that surface is exposed to light will it convert to Cr3 or does it need something to cross link with?

I was almost thinking of adding a flood light as part of the cleaning process :? Not just for that but also unexposed coated plates that need to be reprocessed and those exposed plates that have thicker film and has a touch of orange.
I think there are involved oxidizing of the hydrocarbons, something like heating it on high temperature in presence of the air. When 'neutralizing' Cr6 with H2SO3 or sodium bisulfite, it change color first to green, then to blue. Blue is indicator that it is mostly Cr3.

Try two things to prove that:

1. Dilute small amount in pure water
2. Dilute the same amount + sugar

Then use UV lamp (longwave, 365 nm) and illuminate that two solutions (or leave in sunlight if you have sunny day). I bet water solution with AmDi in it will not change color, or will change color to yellow. And, solution with mixture of sugar + AmDi should turn brown, or even red/brown.

My $0.02

Best--
milan
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