Procion Dyes

Harold Cohen's use of technology was always pragmatic, in that he used its affordances as means to achieve his ends, rather than for its pre-existing meanings and associations or as a fetish. It was also realistic, in that Cohen's choice and explotiation of technology reflected his current personal and creative directions expressed through the state of the art in artificial intelligence.

In the 1980s and 1990s, Cohen used Procion dyes to hand-colour, and later robotically colour, plotter drawings of output from successive implementations of his AARON drawing program. Procion dyes are fibre-reactive - they bind to the cellulose in fibres such as cotton and are intended for dyeing fabric for clothes. This means that they also work on cotton paper with plotter ink on, such as the watercolour paper that Cohen coloured AARON's drawings on.

Procion MX colour mixing guide: https://static1.squarespace.com/static/5ac4eb022971149bb6d709d3/t/6023268228d2671563496112/1612916355750/Procion_MX_Color_Formula_Guide.pdf

Once you know the Procion colours, you can see them in Cohen's work (alongside coloured pencil in the second example below):

https://whitney.org/collection/works/67990

https://collections.vam.ac.uk/item/O499587/drawing-cohen-harold/

I suspect but do not know that Cohen used neat Procion MX dye without soda ash added. The results would be as (impermanent) as watercolour. Washing cotton watercolour paper to clean it for wearing is a category error outside a few haute couture moves.

Cohen mentions using Procion, and details of the painting machine: https://tcm.computerhistory.org/CHMfiles/Harold%20Cohen,%20%20Robotic%20Artist,%201995.pdf

Cohen discusses the challenges of working with the dyes programatically for the painting machine:

https://www.aaronshome.com/aaron/publications/colouringwithoutseeing.pdf

https://www.kurzweilcyberart.com/aaron/pdf/furtherexploits.pdf

When high-quality large-format inkjet printers became available, Cohen switched to them with his usual pragmatism. He said that he preferred their wider gamut (I forget where he said this, it may have been in one of his talks in the UK I attended).

This means that colouring machine drawings with Procion is now, like pen plotting itself, a historical medium. In digital terms it is to contemporary digital art as woodcut was to oil paint in tubes for the Expressionists. Or as record static and scratches were to musicians using digital samplers.

Historical, or dead, media are orphaned from pragmatism and realism in the sense of not being state of the art. Their arms races of instrumental quality (ever-increasing recording fidelity, ever brighter colours, etc.) end, and they become visible as things in themselves rather than means to ends, their qualities evaluated formally and aesthetically. Their noise becomes a signal. Their limits become integrals. Brian Eno and Rosalind Krauss popularized this understanding.

If you need a historically grounded human touch to your machine drawings underwritten by the discourses of art theory, colouring them with Procion by hand is something you can explore to deepen your engagement with the medium's history. Even if you don't end up using it in finished works, copying the masters has always been part of an artist's stylistic development.

(Header image from https://www.jacquardproducts.com/procion-mx-sets )