What is Scratchboard?
Scratchboard is a two-dimensional subtractive medium. Professional grade scratchboard is a three layer substrate consisting of a an archival masonite board that is coated with a layer of kaolin clay and then sprayed with a layer of black India ink. Images are worked in reverse with the artist scratching in the light and highlights rather than the traditional working of shadow to light. However, the images created are not negatives. Scratchboard allows for the creation of highly detailed and very realistic images due to the exacting nature of the board and tools.
Artists use sharp implements like craft knives, scalpels, and needles or abrasives like sandpaper and fiberglass brushes to create their images one mark at a time by using the tools to remove the black ink which reveals the white clay beneath. Tonal variations are created by the width and depth of scratches made in the board as well as the amount of black ink removed in a particular area. Small mistakes can be corrected by re-inking an area, but it can be an unforgiving medium. Artwork may be left black and white or the revealed clay may be colored by using colored inks. Images are created with thousands upon thousands of lines, dashes, and dots. They may take many many hours depending upon the size and complexity of the composition.
The boards used by many professionals in this medium are archival and highly resistant to fading and yellowing. Additional protection is added to finished pieces with an archival varnish. Only the best materials will do if you are going to spend dozens or even hundreds of hours on a piece of artwork.
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