Lithography: the process
Lithography is a planographic form of printing. It differs from other processes where the image is raised (Lino/Woodblock), or recessed (intaglio: copper/wood engraving or etching). Lithography depends on the interaction of two incompatible substances, grease and water, on a prepared flat surface. The means of making marks on the stone/plates are very similar to those used for drawing/painting and consequently artists immediately feel comfortable using them, unlike having to come to terms with handling an etching needle on copper plate for example.
Once the artist has completed the drawing, the prints are created on presses where an alternate use of damping and inking ensures that only the artist's drawn image receives the application of ink which, when printed on suitable paper, provides the lithographic print. The choice and number of colours available in our printing process is unlimited, giving greater flexibility to the artist.
The lithographic method on stone is the original process as discovered by Alois Senefelder at the end of the 18th century. An abundance of fine grain limestone occurred where he lived in Bavaria and this material formed the basis on which his experiments were made. The concept was based on chemical interaction of grease and water on the flat surface of a prepared limestone block.
He discovered that marks made in this way, with chemical treatment, could be made to accept printing ink, whereas the undrawn areas dampened with water, remained free of ink. Stone has become an attractive printmaking method for artists ever since, offering possibilities of interpretation that are much closer to the use of traditional artists’ materials - crayons, inks, diluted washes and over printed colour etc. Stone is reusable and the artist can select an individual grain to suit the nature of the work to be done. Apart from normal graphic processes involving brush work and crayons, the stone can be engraved, etched with acid and even photosensitised, if required.
The same process works with grained zinc plates. It is also possible to draw onto transfer paper using the same grease based materials and the image is then transferred to either stone or zinc plate. This gives more freedom to the location of drawing, allowing the artist to work freely in their studio, or on location. Once the image has been transferred to the surface it is possible to make additional marks.
Stone and Zinc Plate (autographic)
Marks can be drawn directly onto the surface using grease-based substances, from lithographic crayon, to tusche washes. If the drawing needs to be done on location and the thought of carrying a stone or plate around is unappealing, then there is the option of drawing onto a specially prepared transfer paper using the same drawing materials. Once the mark making is complete, the image is transferred directly onto the chosen surface. Should further drawing be required at this stage that is possible too. The texture of the stone and plate can also be chosen, as both can be ground to the required coarseness. Zinc plate can be printed from a direct or an offset press. These are continuous tone processes.
Polymer coated photo plate (autographic)
There are a number of ways of approaching this process, but for ease of description, the artist draws directly onto a film or paper that has a degree of translucency and all the information is transferred to the plate by exposure under UV light.
This method doesn't require the use of grease-based substances as the polymer coating mimics the properties of grease. If a multi-colour image is required, a separate drawing is made for each colour making use, if desired, of the overlap. Because the artist is free to use any substance (not grease based) they can also make use of stencils, or even objects to recreate unusual marks - it really is only limited by the artists own exploration. This is a continuous tone process.
Reproduction use of polymer coated photo plate
This process is used for making a print from an existing image. First a transparency, scan or high resolution digital file is needed, from which a set of films are made in order to transfer the information to plate. In the case of four-colour work, we add additional spot colours to regain the vibrancy and depth often lacking in most commercial colour printing. It is possible to use this process in conjunction with hand drawn plates.
We have developed a process for photography that allows us to print a continuous tone photographic image, which means that the quality of the image is not lost by being broken up by dot screens.
The photograph is transferred to plate without being scanned and then printed in layers capturing all the richness and tones of the original. We are still developing a similar system for full four-colour photography. You can also use this method with hand drawn plates. This is a continuous tone process. (Patent applied for)
The process of mono-printing can offer artists an extremely versatile way of working, enabling them to create a range of unique pieces of work instead of an edition of the same image. Artists have enjoyed the flexibility and experimentation this method offers. Marks can be made in many different ways, for example using developer on photo-plates as a drawing medium, wiping ink off or scratching it away, tissue stencils, reduction technique and painting ink directly onto the bed of the press. Our presses can transfer very subtle and delicate marks, with quick and exciting results.