Re: Gum prints with the enlarger

Judy Seigel (jseigel@panix.com)
Tue, 23 Apr 1996 17:23:54 -0400 (EDT)

On Wed, 24 Apr 1996, Philip Jackson wrote:
> Mike mentioned the professional literature on dye sensitization associated
> with the photo-hardening of colloids. Just recently I've been looking into
> dye sensitized vinyl monomers as an alternative to dichromated gelatine. It
> sounded very simple: a vinyl monomer in aqueous solution (7% acrylonitrile
> in water), a photoreducible dye (rose bengal), a mild reducing agent or
etc.

Hi Philip, Good to hear from you again, and as soon as my evil service
provider decides to let me download again (it never seems to run out of
evil tricks!) I will download & print out the bibliography you provide.
Amazing -- and a girl never knows when she needs something really amusing
to try out.

Meanwhile, by cosmic coincidence I suppose, an American Photography
magazine of May 1917 bought at the APHS fair on Sunday has an item
headed "Dyes as Sensitizers of Carbon Tissue and Gum Paper," that begins:

"In a recent issue of the British Journal of Photography a very
interesting article of unusual import to pictorial workers furnished data
which will doubtless be the basis of many experiments in the near future.
We quote verbatim:

"'In the Danish Amateur-Fotografen for January is an article by Hans
Waago, discussing a new and entirely original method of sensitizing
carbon and gum papers with weak dye solutions. The process is based on
what appears to be a brilliant scientific discovery [once in 200 years?],
as far as I am aware, of hitherto unsuspected properties of substances
...[substituting for] bichromates and chromates weak dye solutions of
1-1000 to 1-10,000 dilution....the paper keeps indefinitely in a
sensitive condition [but] must be used damp....'"

I'm not going to copy more here (article goes on for another page or so),
since I assume this is known and/or obsolete information. The dye he
cites is erythrosin, for the most part, plus auramin, along with some other
technical information that was really too simple for me to deal with ;-).

He also says "the description of the modus operandi is based both on Dr.
Meisling's personal communications to the author of the Danish article,
and on his articles in the 'Dansk fotografisk Tidsskrift.' (Parts 9 & 10,
1916.) Already in 1908 prints on paper sensitized with aniline colors
were shown ...before the Royal Danish Scientific Society."

Judy