The object I have brought and the image that you see in the photograph to represent my tool is of a sheet of rolled True Grain film. True Grain is the product name of one type of film positive.

Technical Description

A ‘film positive’ is a technical term and the definition of an intermediate object used in the printmaking process to make a stencil in lithography, and screen printing. It is a translation tool which contains information of areas that are to be transferred to the matrix, that will then let ink pass through them and, will print as a positive mark on the substrate being used. These positive areas are transferred to the matrix through different methods depending on the printmaking process being used.

The film itself is a support material for the artwork to be applied or, adhered to. Films can be used singularly to eventually be printed in one colour or, or multiple films can be used to overprint to produce multiple colours.

The process of transferring the film positive to the matrix is a chemical one and one that uses photographic processes. In screen printing for example; the screen mesh is initially coated with a light sensitive photographic emulsion. When dry, the film positive is then placed in tight contact with the emulsion. UV light is passed through the film positive onto the emulsion. The positive opaque areas of the film mask and prevent the emulsion behind it in those areas from receiving UV light. Where there is no positive mark on the film the UV light is able to pass and, burn the emulsion securely to the mesh. The emulsion is then washed away removing the unburnt emulsion, creating a positive stencil. These areas will then allow ink to pass through them and to be printed onto the substrate below.

Stencilling, or masking within printmaking is conceptually as much a process not dissimilar to drawing, where representational lines and marks can be made to define the form of an object. Film positives can also then be used to create tone, and colour. We can also work formally to work with scale.

Types of film positive

True Grain TM http://www.johnpurcell.net/true_grain_Rev.pdf
Acetate
Inkjet film positives
Rubylith Film
Lith film
Paper & card stencils
Laser printer paper
Flat objects