The use of image analysis in the production control and final print characterisation of printing inks and toners

A great deal of work when characterising printing materials and finished substrates coated with printing inks and toners utilises microscopic examination. Coates Electrographics is involved in a range of electronic-printing-related areas, and image analysis provides a very useful tool in quality control and development for quantifying microscopic analysis. An off-the-shelf Optomax V Image Analyser with Insight frame grabbing capability, combined with software provided by the supplier, is used. This enables a number of very useful measurements and image processing functions to be applied. The video image is captured from the microscope by a CCD camera which provides good resolution, high sensitivity and variable gamma. The paper discusses three applications; the measurement of resist coating thickness over copper laminate PCBs; the assessment of the effectiveness of separation of filtration on finely dispersed pigmented jet inks; and the evaluation of nonimpact printed toner adhesion to bond paper by measurement is a crease test