Printmaking falls into two categories – ‘Relief’ where the image is raised above the surface of the printing plate, and ‘Intaglio’ where the image is incised below the surface.
Prints are usually made from metal plates, lino and water-protected card, but you can also ink up anything with a texture – leaves, fabric – and achieve an image.
I primarily work in intaglio and there are two principal ways to do this:
Zinc, copper or steel plates – a new plate starts out clean and shiny, almost like a mirror, and a design is eaten into it using acid which literally dissolves the metal. When I am designing a plate I put a ‘resist’ (something to keep the acid out) on areas of the plate where I want to keep the plate clean and smooth, and I leave the surface open where I want the acid to get access to the metal and eat away at it.
Parts of the plate that remain shiny will not hold ink because there is nothing to grip it, but where I have let the acid eat the plate I can subsequently apply ink and the plate will retain it and transfer it – print it – on wet paper.
As a ‘resist’ I can use wax crayon, permanent pen or special strong protective solutions called ‘stop out’ or ‘hard’ and ‘soft ground’. If I want to transfer a photograph to the plate there is a special liquid I can use called photo-sensitive film which I roll onto the plate like paint and then expose using a light box.
Collagraph – To achieve subtle textured effects, or as a cheaper alternative to a zinc plate I can also take prints from card which is then varnished to protect it from the ink and pressure as it goes through the press. I can cut into the card or apply textures to it – sand, lace, card – to achieve the effect I want.
Lino cut, Relief printing – Another option is to use special cutting tools to cut a design into a piece of printmaker’s lino. This comes in different thicknesses. Ink is then rolled over the surface of the lino and pressed onto dry paper to print.
Silk screen Printing – A final option is to apply an image by hand or photographically to a silk screen and then to use a squeege to push ink through the screen and onto dry paper. Colours can be built up by having different screens, each with a different part of the final image, reserved for different colours.