Furthermore, because the paper used is damp, water-based inks may result in the image bleeding. Intaglio ink is oil-based, as water-based inks can dry too quickly on the matrix. If the ink is too soft, some pigment may be added. If the ink is too stiff, a little boiled linseed oil may be added, or the plate may be warmed on a hotplate – but not too hot, or a metal matrix may be damaged through buckling or cracking. A portion of ink is set out on the slab and worked with a knife or palette knife to ensure it is neither too stiff nor too soft, and that there is no dried ink or foreign matter present. A glass or marble slab is ideal, but any very smooth surface can be used. As with relief printing, there needs to be a flat, clean, smooth surface for the printing ink. For more information, see File Your Edges.Ībove: the filed edge of the Luna copper plate
This prevents the sharp metal edges of the plate from cutting the paper, or the blankets of the press. They are filed down at a 45 degree (approximate) angle away from the upper surface. However, in essence, the modern method is still very close to its 15th Century counterpart.Ībove: my etched copper plate, copied from the engraved image ‘Luna’ by Hans Sebald Beham, printed in 1539īefore the very first printing of a prepared metal plate, the edges must be filed. Some of the equipment/method used will be modern, but this will be noted. The process of producing the actual matrix will be described in another post – this is a discussion of the basic printing process – however it is worth noting that the three main methods of producing an intaglio plate before 1600 were engraving, drypoint, and etching. In this post, I’ll be using an etched copper plate as the matrix to describe the intaglio printing process.
Jewellers and sculptors had been using this method since antiquity, but it was not until the 1430’s in Western Europe that this technique was first applied to a flat piece of metal with the express purpose of transferring the image to paper. The word intaglio comes from the Italian intagliare, to cut, and refers to the method of cutting, or incising, lines into a surface, to produce an image. When ready for printing, ink sits in the lines below the surface of the matrix, and pressure is applied using a rolling motion with an intaglio press, forcing the ink out of the inked lines in the matrix onto the paper. In the intaglio method of printing, we are talking about using a matrix which has the image below the surface.