Ghosts in screen printing - what is it?

Ghosts in screen-printing are the characteristic haze created by microscopic deposits from previous treatments. The ink flow is impeded by the deposits on the screen, which results in the formation of latent images or ghosts. It is therefore crucial to clean the master thoroughly after each print. Using dirty grids not only results in ghosting, but also leads to damage to the matrix structure.

Most stains can be easily removed with suitable solvent-based cleaners to prevent discolouration of the screen mesh. The mesh cleaner is applied with a brush to both sides of the matrix until the ink is dissolved. The mesh should then be thoroughly rinsed with water using a high-pressure gun. It is worth knowing that fogging products are strong chemicals, so they must be handled with care.

What is screen printing?

Screen printing is used to print on a variety of surfaces such as paper, fabric, plastic, wood, foil and many others. It is a very versatile method that guarantees high quality and long-lasting prints. Screen printing is mainly used for large print runs- for smaller quantities, screen printing is not cost-effective due to the need to prepare the matrix. During printing, a screen mesh is applied to the printing form, which serves as a template for the print - unprinted elements are covered and the ink only flows through the open gaps. The mesh is usually coated with a special photosensitive emulsion, which is exposed and developed. Any ink deposits on the grid left over from previous printing cycles can therefore significantly reduce the quality of the print and contribute to defects in the form of fogging.