Photo Engineer
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Many years ago, Grant Haist wrote that faster fix and wash rates could be achieved by using a method to swell gelatin. Using bone gelatin, he suggested formulating a high pH fixer which would maximize swell and thus accelerate fix and wash rates. The result we have today is TF-3 and TF-4.
While his work was going on in B-82 at KP, just down the street in B-59 a team was working on other means. This included a variety of methods. I'm going to list a few here.
1. Mix fixing agents that are superadditive in fix rates (only affects fix rate normally, but low molecular weight or small fixing agents will also improve wash rate).
2. Add an agent to induce greater gelatin swell without damaging the emulsion. This improves fix and wash rates.
3. Higher pH and a combiation of the above. Improves fix and wash rates.
4. Add an agent that promotes silver metal image stability if any is left in the coating. Allows shorter wash times.
There were 3 of us working on this approach for fixes and blixes. There was another team working on a conventional approach.
But, using some combination of the 4 above, a huge reduction in fix and wash times for silver halide materials can be achieved as well as a true blix for color film. In fact, the fix time can be made to approach the clear time and the actual diffusion rate of chemistry into and out of the coating. On modern films this is on the order of 15" - 30" at 20 deg C.
My Super Fix, poste here one time or another and on Photo Net as well, is an early example of one such fix.
Well, I am on Super Fix VIII, and I can say that after about 3 years, it works. I can say though that I finally have a high speed fix that washes out rapidly, is odorless, and has high capacity. It uses all of the above listed methods and is a result of nearly 30 years study of bleaching, fixing and washing. Bill Troop and I have worked on this quite a bit over the last few years and hope you will enjoy it if/when it is finalized.
PE
While his work was going on in B-82 at KP, just down the street in B-59 a team was working on other means. This included a variety of methods. I'm going to list a few here.
1. Mix fixing agents that are superadditive in fix rates (only affects fix rate normally, but low molecular weight or small fixing agents will also improve wash rate).
2. Add an agent to induce greater gelatin swell without damaging the emulsion. This improves fix and wash rates.
3. Higher pH and a combiation of the above. Improves fix and wash rates.
4. Add an agent that promotes silver metal image stability if any is left in the coating. Allows shorter wash times.
There were 3 of us working on this approach for fixes and blixes. There was another team working on a conventional approach.
But, using some combination of the 4 above, a huge reduction in fix and wash times for silver halide materials can be achieved as well as a true blix for color film. In fact, the fix time can be made to approach the clear time and the actual diffusion rate of chemistry into and out of the coating. On modern films this is on the order of 15" - 30" at 20 deg C.
My Super Fix, poste here one time or another and on Photo Net as well, is an early example of one such fix.
Well, I am on Super Fix VIII, and I can say that after about 3 years, it works. I can say though that I finally have a high speed fix that washes out rapidly, is odorless, and has high capacity. It uses all of the above listed methods and is a result of nearly 30 years study of bleaching, fixing and washing. Bill Troop and I have worked on this quite a bit over the last few years and hope you will enjoy it if/when it is finalized.
PE
