Oil print process
The oil print process is a photographic printmaking process that dates to the mid-19th century. Oil prints are made on paper on which a thick gelatin layer has been sensitized to light using dichromate salts. After the paper is exposed to light through a negative, the gelatin emulsion is treated in such a way that highly exposed areas take up an oil-based paint, forming the photographic image.
Greasy ink is repelled from a gelatin that is swollen with water while hardened gelatin accepts the ink. The oil pigment process works on the same principle as lithographic printing > oil and water don’t mix.
The oil print process creates soft images reminiscent of paint or pastels but with the distinctive indexicality of a photograph.
As with other forms of printmaking, the ink application requires considerable skill, and no two prints are identical.
Each print is unique.
Oilprints have a great decreased susceptibility to deterioration compared to silver-based prints due to the inherent stability of the process and also because they are commonly printed on 100% cotton rag papers. No silver metals are involved that could destroy the paper.
Oilprints, dating around 1910, are still in good condition in several museums/collections around the world.
Short description of the process
1/ Preparing watercolour paper. The luxury paper weights 300gr and is 100% cotton.
2/ Preparing the high quality photographic gelatin.
3/ Pouring the gelatin onto the paper. Drying the gelatin layer > +- 24h.
4/ Sensitizing the gelatin layer with liquid sensitizer.
5/ Creating digital negative on transparant sheets. Negative has same size as the print.
6/ Expose the print under UV light source.
7/ Develop the print by washing in water to remove the unexposed sensitizer. (example)
8/ Dry the washed, uninked print during 24h (example)
9/ Soak the print in water to swell the gelatin.
10/ Ink the print with lithographic ink.