Specifications

Specifications are a means of communication between customer and supplier. They should be developed cooperatively.

To keep processes under control, ink manufacturers specify and test both raw materials and finished products.

Statistical Quality Control (SQC) and Statistical Process Control (SPC) emphasize the urgency of working with the right materials.

The specifications must be developed to assure the printer gets a product which performs properly in the printing plant.

Color is a difficult property to specify. It depends on substrate and ink film thickness. Usually colored ink is specified colorimetrically by CIELab value.

The acceptable tolerance (?E value) needs to specified as well as the substrate and film thickness.

Color Strength can be determined with a densitometer on a dry ink film. It must be specified as the ink film thickness that can be carried on press to produce the specified optical density.