3M Color-Key. Was: Colour-Key

Luis Nadeau (awef6t@mis.ca)
Wed, 28 Aug 1996 23:10:17 +0300

>Does anyone know of a (rather old) process called "Colour-Key"? I recently
>heard from a photographer of this process, which has been around for thirty
>years or more. He was fairly enthusiastic about it, but has not seen any
>recent examples - he does remember someone using it in 1971! I have not
>seen any examples, and I am not sure whether this is truly an alternative
>process or simply a commercial advertising-style technique for producing
>slick images, posters, etc. The little I know of it is as follows:
>
>The process involves the use of UV-light to make the image: so far so good
>;-) The process can be used to vary greatly the colour of the final image,
>depending on what chemicals are used at the start. It is not, so far as I
>can understand, a full four-colour process, and the basis is either a
>monochrome or two-colour image. It is possible to simply wash away areas of
>the image (which sounds slightly gimmicky and not very permanent to me).
>The process was/is, I think, produced by one company only (?which).

The 3M Color-Key was a "color proofing process" used extensively in the
photomechanical trade. It is almost certainly obsolete by now. Some
printmakers used it to produce fine art prints but the pigments, which
matched printing inks, were certainly not permanent.

The idea of using a color proofing process as an archival printing medium
is not new. The article "Lasercrom" in my Encyclopedia refers to a company
in Kansas that modified DuPont's Cromalin color proofing system, with
permanent pigments (1982) One of the problems is that the pigments layed on
sandwiched plastic layers of dubious archival quality.

In recent times, processes based originally on color proofing systems have
been marketed. The EverColor process, based on AgfaProof, but using
permanent pigments, is proprietary. One has to go through EverColor to have
prints made. Another process with which one can buy materials and make
prints from color separations, is the UltraStable, marketed by Charles
Berger, who normally lurks on this list. If you do a search on
"UltraStable" you should find a site that describes how the process works.

I have specimens of both processes in my collection and they are superb.

Luis Nadeau
awef6t@mis.ca
Fredericton, New Brunswick, Canada
http://www.mi.net/dialin/awef6t/