bmaxey1@juno.com
Date: 09/09/01-03:21:34 AM Z
>>Technicolor's processes were highly proprietary. I doubt if actual
>>formulas were ever published. The patent literature may have some clues
but
>>hundreds of patents were issued to Technicolor over the years.
I am not sure they were either, but that mattered little, as no one
except Technicolor would have attempted to do what they did so well. All
you would have needed were the dyes - available at the time from Kodak,
the Matrix Film, also available, ... everything was available, so there
were not really any big secrets except for the equipment and cameras. IB
required extreme precision, accurate registration and extremely
complicated cameras and knowlewdgeable technical people.
NO ONE would have considered trying to compete with a similar process.
Technicolor did it best and that is why they were the kings of color at
the time.
There is lots of technical info about other Dye Transfer processes,
however.
>>I tried to find formulas for some tanning developers. Its surprisingly
>>difficult, none of my usual sources have any. I think the formulas for
the
>>Kodak Wash Off Relief process were published and perhaps also for its
>>successor, the Dye Transfer Process, which is essentially similar. Both
are
>>very similar to the Technicolor IB process. In fact, Kodak made all the
>>photographic material for Tech.
Dupont and others published these developer formulas. As for Kodak - I am
looking at a DT Process guide right now, published in the late '40s with
tanning developer formulas, and mordant formulas. I also have the same
formulas from Polaroid for use with their Vectograph Process. They are
available, but no one cares these days as their use is no longer
possible.
>>I did find some example formulas in _History of Color Photography_
Joseph
>>S. Friedman, Phd, 1944, Boston, The American Photographic Book
>>Publishing Co. I believe there is a reprint edition of this book.
>>In any case, Friedman has a great deal of stuff on Technicolor (for
whome
>>he worked at one time) and quotes some sample tanning developers, not
>>necessarily those used by Technicolor. He quotes E.J.Wall (who also
worked
>>for Technicolor, but much earlier).
>Formula No.1
>Metol 1.5 parts
>Hydroquinone 1.5 parts
>Sodium Sulfite 2.0 parts
>Sodium Carbonate 17.5 parts
>Potassium Bromide 1.5 parts
>Water to 1000.0 parts
>
>No. 2
>Hydroquinone 4.0 parts
>Sodium Sulfite 2.0 parts
>Sodium Carbonate 15.5 parts
>Potassium Bromide 1.0 parts
>Water to 1000.0 parts
> >
>Friedman also quotes a Technicolor patent, USP 1,919,673
>
>Pyrogallol 8.0 parts
>Sodium Hydroxide 3.0 parts
>Ammonium Chloride 1.5 parts
>Potassium bromide 1.5 parts
>Citric Acid 0.2 parts
>Water to 1000.0 parts
>
>>There are almost certainly better practical formulas.
>>The wash-off relief process, and the dye transfer process use a bleach
to
>produce the tanning effect. The matrix was developed in a normal active
>film developer like DK-50 and bleached in an acid dichromate bleach
>containing a halide (chloride). The resulting film was then "developed"
in
>hot water to produce the relief image. There is more to it than this but
>this is the essential.
This is incorrect. A special tanning developer was used. Matrix film was
exposed and then processed in tanning developers and NOT a separate
developer and bleach process. IT was a simple, straight forward process.
>>Its possible that Technicolor used this sort of indirect tanning rather
>>than a direct tanning developer. Unfortunately, the retired Tech people
I
>>knew are all dead so I have no one to ask.
If you understand the process Technicolor used, you would know it was
essentially the same as the Dye Transfer Process. All printing was done
directly to matrices and then printed to a clear base that was mordanted.
This allowed acceptance of the dyes.
>>There have been attempts to resurect the Kodak Dye Transfer process. I
>>don't know if anyone is making materials now.
Kodak made matrix film special for the last iteration of the IB Process,
and no, they will not make materials available to others. I know there
has been a great deal of money offered to Kodak for special runs of
Matrix Film, but Kodak says no. This is very curious as the group I am
aware of could easily meet Kodak's order requirements. The way Kodak
abruptly discontinued the matrix film upset lots of us because we were
assured we would have time to order. The requirements for a suitable film
are simple, and it would be a simple film to make, but interest seems to
be dropping off. Too bad, as no color process will compete with the DT
Process. Other manufacturers would have no problem either, as several
people I know have these emulsion formulas.
>>Its very likely that the actual Dye Transfer formulas are available, I
>>just don't have them. Someone on this list may have formulas or even be
>>using the process.
Yes, they are available. I know of one gentleman who offered his specific
and exact process for making matrix film, dyes, and mordant/conditioner
on the Internet. From mixing, through noodleing to coating; as well as a
companion developer.. The Dye Transfer Company in Texas(?) also tried to
sell their version of matrix film, but I am not sure if still available.
As for my involvement, I have made many such prints. I did this when I
ran a lab for my last photographic assignment.
HCM
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